Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Printed electronics are expected to be implemented as a set of industrial technologies that will facilitate the on-demand fabrication of imperceptible[1] and shapeable[2] devices. Conductive pastes are typically composed of polymeric matrices with embedded conductive fillers. The properties of the fillers can be exploited to deliver functional devices as printed transistors[3], displays[4] and sensors[5]. The smart integration of such elements will allow task-specific integration in consumer electronics and even personalized wearable devices.
Aiming to develop on-skin printed interfaces, it is necessary to ponder mechanical, performance, and health safety considerations. Integrating magnetic sensors on interactive platforms is attractive due to their touchless, action-at-distance nature, which increases the reliability of the devices[6]. In the past, solution processable magnetic field sensors have been fabricated from composite pastes embedding magnetic particles. Among the previous reports on printable magnetic sensors, there are not examples of devices able to maintain high performance sensing during usual skin deformations[7]. Concomitantly, there is a lack of research on skin-compliant printed magnetic sensors able to perform below the 40 mT safety continuous exposure threshold established by the World Health Organization[8].
Here, we will present the fabrication and implementation of stretchable printed magnetic field sensors. They are based on composite pastes with embedded flakes of [Py/Cu]30 Giant Magnetoresistance (GMR) thin-film stacks. We demonstrated printed GMR sensors on ultrathin (3-µm-thick Mylar) foils which are skin compliant, and with maximum sensitivity at 0.88 mT. The stretchable sensors maintained stable sensing performance at 16 µm bending radius and 100 % strain which corresponds to two orders of magnitude increase with respect to previous reports. We demonstrate the implementation of the technology on interactive applications after laminating the printed sensors on the user's skin to navigate through digital maps and scroll through text documents. The ability of the sensor to comply with the skin creases and deformations, and to detect field changes in the safe threshold limit, place this technology as a prospective method for fabricating on-demand printed human-machine interfaces[9].

[1] M. Melzer et al., Nat. Commun. 6, 6080 (2015)
[2] D. Makarov et al., Appl. Phys. Rev. 3, 011101 (2016)
[3] J.A. Lim et al., Adv. Func. Mater. 20, 3292 (2010)
[4] S. Cho et al. ACS Appl. Mater. Interfaces 9, 44096 (2017)
[5] X. Wang et al. ACS Appl. Mater. Interfaces 10, 7371 (2018)
[6] P. Makushsko et al., Adv. Func. Mater, 2101089 (2021)
[7] E.S. Oliveros Mata, et al. Appl. Pys. A 127, 280 (2021)
[8] Static Fields. World Health Organization. (2006)
[9] M. Ha, E.S. Oliveros Mata, et al. Adv. Mater. 33, 2005521 (2021)

Gezieltes Herauslösen von Substanzen aus Roh-und Reststoffen mit biologisch basierten Aufbereitungstechnologien
Identifizierung und Verwendung von Material spezifischen Biomaterialien in der
Ressourcenrückgewinnung

Generation of arbitrarily spin-polarized lepton (here refer in particular to electron and positron) beams has been investigated in the single-shot interaction of high-energy polarized γ photons with an ultraintense asymmetric laser pulse via nonlinear Breit-Wheeler (BW) pair production. We develop a fully spin-resolved semi-classical Monte Carlo method to describe the pair creation and polarization in the local constant field approximation. In nonlinear BW process the polarization of created pairs is simultaneously determined by the polarization of parent γ photons, the polarization and asymmetry of scattering laser field, due to the spin angular momentum transfer and the asymmetric spin-dependent pair production probabilities, respectively. In considered all-optical method, dense GeV lepton beams with average polarization degree up to about 80% (adjustable between the transverse and longitudinal components) can be obtained with currently achievable laser facilities, which could be used as injectors of the polarized e+e− collider to search for new physics beyond the Standard Model.

Deep understanding of the impact of photon polarization on pair production is essential for the efficient generation of laser-driven polarized positron beams and demands a complete description of polarization effects in strong-field QED processes. Employing fully polarization-resolved Monte Carlo simulations, we investigate correlated photon and electron (positron) polarization effects in the multiphoton Breit–Wheeler pair production process during the interaction of an ultrarelativistic electron beam with a counterpropagating elliptically polarized laser pulse. We show that the polarization of e−e+ pairs is degraded by 35% when the polarization of the intermediate photon is resolved, accompanied by an ∼13% decrease in the pair yield. Moreover, in this case, the polarization direction of energetic positrons at small deflection angles can even be reversed when high-energy photons with polarization parallel to the laser electric field are involved.

In their article [Phys.\ Rev.\ C {\bf 100}, 064610 (2019)], Lv, Duan, and Liu study the enhancement of deuterium-tritium fusion reactions by the electromagnetic field of an x-ray free-electron laser (XFEL). While we support the general idea (which was put forward earlier in our rapid communication [Phys.\ Rev.\ C {\bf 100}, 041601(R) (2019)]), we find that the time-averaged potential approximation used by Lv, Duan, and Liu is not justified in this regime and does not take into account important effects. Due to those effects, the enhancement mechanism may actually be more efficient than predicted by Lv, Duan, and Liu.

The study of magnetohydrodynamic (MHD) instabilities occurring in liquid metals, with
imposed differential rotation and magnetic field, is of fundamental importance in the astrophysical
context. MHD instabilities are especially relevant in planets or stars, where electrically conducting
flows are confined within their interiors. Such environments could be modeled by solving the
Navier-Stokes and induction equations with appropriate conditions in a spherical shell composed of
two concentric spheres. In particular, we consider the case where the liquid metal (GaInSn in our
case), bounded by a stationary outer sphere and a uniformly rotating inner sphere, is subjected to an
axial magnetic field. When the aspect ratio of the radii of the two spheres is fixed, only two
parameters, namely, the Reynolds number (associated with the differential rotation) and the
Hartmann number (associated with the applied magnetic field strength), govern the dynamics of the
system (see [1,2] for full details).
For the magnetized spherical Couette system, three different types of instabilities have so far
been identified and characterized by means of numerical simulations (e.g. [1,3]), and also in
experiments (e.g. [2,4]). These instabilities can each be described as a hydrodynamic radial jet
instability, a return flow instability, and a Kelvin-Helmholtz-like Shercliff layer instability. We
provide an overview of these instabilities with a focus on the description and analysis of the
different spatio-temporal symmetries of the MHD flow. In particular, numerical and experimental
bifurcation diagrams of nonlinear waves in the quasi-laminar regime (with moderate differential
rotation) are presented and some numerical tools, related to nonlinear dynamics and chaos theory
[5], are outlined. These tools include the numerical continuation of periodic solutions and their
stability assessment, time series analysis such as the computation of the fundamental frequencies in
one or several spatial dimensions, time dependent frequency spectra, and Poincaré sections.
Our results show how periodic and quasiperiodic MHD flows with two, three and even four
incommensurable frequencies, as well as MHD chaotic flows, are developed following a sequence
of bifurcations from the base state. The knowledge of the different routes to chaos is of fundamental
importance in turbulence theory. In addition, by taking into account the symmetries of the solutions
several regions of multistability (and also hysteretic behavior) are identified in the parameter space
with a good agreement between simulations and experiments, both in their temporal and spatial
structures. Although unstable MHD flows are not experimentally realized, their numerical
computation as in [1,6] provides a more complete picture of the dynamics and aids the
understanding of transient and hysteretic behaviors in experiments.
This work is funded by the European Research Council (ERC), Horizon 2020 research and
innovation programme (grant agreement No. 787544). The authors wish to thank Kevin Bauch for
technical support.

1. Garcia, F. and Stefani, F., Continuation and stability of rotating waves in the magnetized spherical Couette
system: Secondary transitions and multistability. – Proc. R. Soc. A (474), 2018. – p. 20180281.
2. Ogbonna, J., Garcia, F., Gundrum, T., Seilmayer, M. and Stefani, F., Experimental investigation of the return
flow instability in magnetized spherical Couette flows. – Phys. Fluids (32), 2020. – p. 124119.
3. Travnikov, V., Eckert, K. and Odenbach, S., Influence of an axial magnetic field on the stability of spherical
Couette flows with different gap widths. – Acta Mech. (219), 2011. – p. 255.
4. Kasprzyk, C., Kaplan, E., Seilmayer, M. and Stefani, F., Transitions in a magnetized quasi-laminar spherical
Couette flow. – Magnetohydrodynamics (53), 2017. – p. 393.
5. Kuznetsov, Y. A., Elements of Applied Bifurcation Theory, 2nd Edition – Springer, New York, 1998.
6. Garcia, F., Seilmayer, M., Giesecke, A. and Stefani, F., Four-frequency solution in a magnetohydrodynamic
Couette flow as a consequence of azimuthal symmetry breaking. – Phys. Rev. Lett. (125), 2020. – p. 264501.

An overview of the nonlinear dynamics of the magnetised spherical Couette flow is presented. This problem is fundamental for understanding magnetohydrodynamic MHD instabilities occurring when a liquid metal flow, driven by the rotation of the inner boundary in a spherical shell, is subjected to an axial magnetic field. The analysis, at a moderate rotation rate and applied magnetic fields, is based on direct numerical simulations and numerical tools from dynamical systems and chaos theory, as well as laboratory experiments. Several type of MHD waves are classified and a reasonable agreement between simulations and experiments is obtained.

Experiments on the magnetised spherical Couette system are presently being carried out at Helmholtz-Zentrum Dresden-Rossendorf (HZDR). A liquid metal (GaInSn) is confined within two differentially rotating spheres and exposed to a magnetic field parallel to the axis of rotation. Intermittent chaotic flows, corresponding to the radial jet
instability, are described. The relation of these chaotic flows with unstable regular (periodic and quasiperiodic) solutions obtained at the same range of parameters is investigated.

The pulmonary surfactant (PS) is a complex mixture of lipids and proteins dispersed in the aqueous lining layer of the alveolar surface. Such a layer plays a key role in maintaining the proper lung functionality. It acts as a barrier against inhaled particles and pathogens, including viruses, and may represent an important entry point for drugs delivered via aerosols. Understanding the physicochemical properties of PS is therefore of importance for the comprehension of pathophysiological mechanisms affecting the respiratory system. That can be of particular relevance for supporting the development of novel therapeutic interventions against COVID-19–induced acute respiratory distress syndrome. Owing to the complexity of the in vivo alveolar lining layer, several in vitro methodologies have been developed to investigate the functional and structural properties of PS films or interfacial films made by major constituents of the natural PS. As breathing is a highly dynamic interfacial process, most applied methodologies for studying PSs need to be capable of dynamic measurements, including the study of interfacial dilational rheology. We provide here a review of the most frequently and successfully applied methodologies that have proven to be excellent tools for understanding the biophysics of the PS and of its role in the respiratory mechanics. This overview also discusses recent findings on the dynamics of PS layers and the impact of inhalable particles or pathogens, such as the novel coronavirus, on its functionality.

In this talk we give an overview of the current state of the developments of the contactless inductive flow tomography (CIFT) for two different cylindrical cells with aspect ratio 1 and 0.5 for Rayleigh-Bénard convection. Both cylindrical vessels are filled with the eutectic alloy GaInSn. We address the challenges in the flow induced magnetic field measurement and show first reconstructions of the complex three-dimensional flow structure in the cell with aspect ratio 0.5.

The development of closed control loops for electromagnetic actuators in continuous casting based on the current flow conditions of the liquid steel in the mold is challenging due to the opaqueness and the high temperature of the melt. In this work we will investigate the applicability of Contactless Inductive Flow Tomography (CIFT) as a real-time measurement technique for controlling the strength of a ruler type Electromagnetic Brake (EMBr) in a model of a continuous caster. Because CIFT relies on the measurement of the small flow induced perturbation of an applied magnetic field, the measurement system is very sensitive to changes of the strength the EMBr. We will shortly delineate the developed compensation method that is able to cope with the non-linearity of the ferromagnetic yoke of the brake. In combination with the real-time reconstruction algorithm for solving the linear
inverse problem, CIFT is able to visualize the flow structure in the mold in real-time with a time resolution of 1 Hz.

As a proof of concept of a closed control loop, we implemented a simple controller which switches the EMBr off, when the impingement positions of the jets at the narrow faces are below a critical threshold. The implemented controller and the experiment will be described in detail.

Highlight talk on the stabilization of proton beam performance enabling a pilot in vivo tumor irradiation study

Explanation on the stable delivery of well-characterized proton bunches for application experiments at Draco PW

Overview on Llaser-driven ion accelerators for applications in radiobiology

After the rediscovery of the normal tissue sparing effect of high dose rate radiation, i.e. the so-called FLASH effect, by Favaudon et al. in 2014, research activities on this topic have been revived and are flourishing ever since. Yet, the exact biological mechanism as well as the required boundary conditions and radiation qualities to reach said sparing remain mostly unclear. We present a laser-based irradiation platform at the Draco PW facility that enables systematic studies into the FLASH regime using proton peak dose rates of up to 10^9 Gy/s. Besides the PW class laser acceleration source, a key component is a pulsed high-field beamline to transport and shape the laser driven proton bunches spectrally and spatially in order to generate homogeneous dose distributions tailored to match the irradiation sample. Making use of the diverse capabilities of the laser driven irradiation platform a pilot experiment of highest complexity has been conducted – a systematic in-vivo tumor irradiation in a specifically developed mouse model. A plethora of online particle diagnostics, including Time-of-Flight, bulk scintillators and screens as well as ionization chambers, in conjunction with diagnostics for retrospective absolute dosimetry (radiochromic films) allowed for an unprecedented level of precision in mean dose delivery (±10 %) and dose homogeneity (±5 %) for the challenging beam qualities of a laser accelerator. The tailored detector suite is complemented by predictive simulations. The talk addresses how our interdisciplinary team overcame all hurdles from animal model development, over enhancing the laser and laser acceleration stability, to dose delivery and online dose monitoring. Results on radiation induced tumor growth delay by laser driven as well as conventionally accelerated proton beams are critically discussed.

In metallurgy, gas is often injected into melts for mixing, degassing or refining. The knowledge of the two-phase flow behaviour is of utmost relevance for optimisation and process control. However, the measurement of the flow structure, the gas distribution and the characteristics of the bubbles is very challenging, because of the opaqueness and the high temperature of industrial relevant melts. Although numerical models have significantly improved recently, it is indispensable to validate the simulation results with experimental data. A new experimental facility has be designed and recently commissioned at Helmholtz-Zentrum Dresden - Rossendorf for systematic investigation of bubble plumes in liquid SnBn at 200 °C. The thermophysical properties of this alloy are very similar to those of steel. The experiment is a 1:5.25 model of an industrial 185 t ladle and consists of a cylindrical vessel with inner diameter of 600 mm, which is filled with 1.7 tons of SnBi. Gas can be injected at the bottom of the vessel at four different locations, which can be equipped with different plug types. Furthermore, low-pressure conditions for modelling VOD (Vacuum Oxygen Decarburization) application can be achieved by the use of a vacuum pump.
The gas distribution was measured by an array of 64 resistive probes with a spacing of 10 mm and a time resolution of 1 kHz. This technique allows also the determination of bubble properties like bubble speed and diameter. The velocity of the liquid was measured by Ultrasound Doppler Velocimetry. The paper provides a description of the new setup in detail and presents measurement results characterizing the bubbly flow for varying gas flow rates and different configurations for gas injection.

The contactless inductive flow tomography (CIFT) allows for reconstructing the mean flow structure of liquid metals by measuring the flow induced perturbations of one or more applied magnetic fields, and subsequently inferring the flow field by solving a linear inverse problem. We will give an overview of the application of CIFT to two models of continuous casting available at Helmholtz-Zentrum Dresden – Rossendorf. These include a 1:8 cold model of a slab casting mould under the influence of an electromagnetic brake, and a 1:2 model of a slab mould operating at 250 °C.

A 33-year-old nursing mother who underwent resection of a glioblastoma of the right hemisphere was referred for a 11C-methionine PET/MR scan to exclude cancer recurrence. In whole-body PETimaging, a slight radiotracer uptake could be observed in themammary glands, reflecting lactation status. In this case report, we initially describe 11C-methionine uptake in the human breast and discuss any consequences arising from this special situation.

The structural inversion symmetry plays an important role in low-dimensional nanomagnets, due to its strong influence on magnetic and electrical properties. It can lead to the appearance of chiral effects, such as the topological Hall effect [1], or to the formation of chiral noncollinear magnetic textures, as skyrmions [2] and chiral domain walls (DWs) [3]. These chiral structures are envisioned to be the key components for realizing novel concepts for magnonics [4], antiferromagnetic spintronics [5], spin-orbitronics [6], and oxitronics [7]. The main magnetic interaction being responsible for the stabilization of chiral magnetic textures is the intrinsic Dzyaloshinskii-Moriya interaction (DMI) [8,9]. It originate in certain magnetic crystals in which the unit cell lacks inversion symmetry, such as the gyrotropic magnetic crystals, or appear typically in ultrathin films or bilayers due to the inversion symmetry breaking on the film interface [3]. At present, tailoring of DMI is done by optimizing materials, either doping a bulk single crystal or adjusting interface properties of thin films and multilayers.

A viable alternative to the conventional material screening approach can be the exploration of the interplay between geometry and topology. This interplay is of fundamental interest throughout many disciplines in condensed matter physics, including thin layers of superconductors [10] and superfluids [11], nematic liquid crystals [12], cell membranes [13], semiconductors [14]. In the emergent field of curvilinear magnetism chiral effects are associated to the geometrically broken inversion symmetries [15]. Those appear in curvilinear architectures of even conventional materials. There are numerous exciting theoretical predictions of exchange- and magnetostatically-driven curvature effects, which do not rely on any specific modification of the intrinsic magnetic properties, but allow to create non-collinear magnetic textures in a controlled manner by tailoring local curvatures and shapes [16,17]. Until now the predicted chiral effects due to curvatures remained a neat theoretical abstraction.

Recently, we provided the very first experimental confirmation of the existence of the curvature-induced chiral interaction with exchange origin in a conventional soft ferromagnetic material. It is experimentally explored the theoretical predictions, that the magnetisation reversal of flat parabolic stripes shows a two step process [18,19]. At the first switching event, a domain wall pinned by the curvature induced exchange-driven DMI is expelled leading to a magnetisation state homogeneous along the parabola's long axis. Measuring the depinning field enables to quantify the effective exchange-driven DMI interaction constant. The magnitude of the effect can be tuned by the parabola's curvature. It is found that the strength of the exchange-induced DMI interaction for the experimentally realised geometries is remarkably strong, namely ~0.4 mJ/m2, compared the surface induced DMI. The presented study legitimates the predictive power of full-scale micromagnetic simulations to design the properties of ferromagnets through their geometry, thus stabilising chiral textures. We explore these curvilinear magnetic thin films for the realization of novel artificial magnetoelectric materials based on curvilinear helimagnets embedded in piezoelectric matrix [20], to enable the geometrical tuning of the magnetochirality in curvilinear 1D architectures [21], tailoring of magnetic states in flat nanospirals [22] and as components of shapeable magnetoelectronics for interactive wearables [23].

[1] N. Nagaosa, et al., Nature Nanotech. 8, 899 (2013)
[2] U. K. Rößler, et al., Nature 442, 797 (2006)
[3] A. Fert, et al., Nature Rev. Mat. 2, 17031 (2017)
[4] A. V. Chumak, et al., Nature Physics 11, 453 (2015)
[5] T. Jungwirth, et al., Nature Nanotech. 11, 231 (2016)
[6] I. M. Miron, et al., Nature 476, 189 (2011)
[7] V. Garcia, et al., Nature 460, 81 (2009)
[8] I. Dzyaloshinsky, J. Phys. Chem. Solids 4, 241 (1958).
[9] T. Moriya, Phys. Rev. Lett. 4, 228 (1960).
[10] J. Tempere, et al., Phys. Rev. B 79, 134516 (2009)
[11] H. Kuratsuji, Phys. Rev. E 85, 031150 (2012)
[12] T. Lopez-Leon, et al., Nature Physics 7, 391 (2011)
[13] H. T. McMahon, et al., Nature 438, 590 (2005)
[14] C. Ortix, Phys. Rev. B 91, 245412 (2015)
[15] Y. Gaididei, et al., Phys. Rev. Lett. 112, 257203 (2014)
[16] J. A. Otálora, et al., Phys. Rev. Lett. 117, 227203 (2016)
[17] V. P. Kravchuk, et al., Phys. Rev. Lett. 120, 067201 (2018)
[18] O. Volkov et al., PRL 123, 077201 (2019).
[19] O. Volkov et al., PSS-RRL 13, 1800309 (2019).
[20] O. Volkov et al., J. Phys. D: Appl. Phys. 52, 345001 (2019).
[21] O. Volkov et al., Scientific Reports 8, 866 (2018).
[22] M. Nord, et al., Small 1904738 (2019).
[23] J. Ge, et al., Nature Comm. 10, 4405 (2019).

The realization of fourfold anisotropic magnetoresistance (AMR) in 3d-5d heterostructures has boosted major efforts in antiferromagnetic (AFM) spintronics. However, despite the potential of incorporating strong spinorbit coupling, only small AMR signals have been detected thus far, prompting a search for mechanisms to enhance the signal. In this paper, we demonstrate an extraordinarily elevated fourfold AMR of 70% realized in CaMnO₃/CaIrO₃ thin film superlattices.We find that the biaxial magnetic anisotropy and the spin-flop transition in a nearly Mott insulating phase form a potent combination, each contributing one order of magnitude to the total signal. Dynamics between these phenomena capture a subtle interaction of pseudospin coupling with the lattice and external magnetic field, an emergent phenomenon creating opportunities to harness its potential in AFM spintronics.

Intense, ultrashort, and high-repetition-rate X-ray pulses, combined with a femtosecond optical laser, allow pump-probe experiments with fast data acquisition and femtosecond time resolution. However, the relative timing of the X-ray pulses and the optical laser pulses can be controlled only to a level of the intrinsic error of the instrument which, without characterization, limits the time resolution of experiments. This limitation inevitably calls for a precise determination of the relative arrival time, which can be used after measurement for sorting and tagging the experimental data to a much finer resolution than it can be controlled to. The observed root-mean-square timing jitter between the X-ray and the optical laser at the SPB/SFX instrument at European XFEL was 308\&\#x00A0;fs. This first measurement of timing jitter at the European XFEL provides an important step in realizing ultrafast experiments at this novel X-ray source. A method for determining the change in the complex refractive index of samples is also presented.

Spatial data mining helps to find hidden but potentially informative patterns from large and high-dimensional geoscience data. Non-spatial learners generally look at the observations based on their relationships in the feature space, which means that they cannot consider spatial relationships between regionalised variables. This study introduces a novel spatial random forests technique based on higher-order spatial statistics for analysis and modelling of spatial data. Unlike the classical random forests algorithm that uses pixelwise spectral information as predictors, the proposed spatial random forests algorithm uses the local spatial-spectral information (i.e., vectorised spatial patterns) to learn intrinsic heterogeneity, spatial dependencies, and complex spatial patterns. Algorithms for supervised (i.e., regression and classification) and unsupervised (i.e., dimension reduction and clustering) learning are presented. Approaches to deal with big data, multi-resolution data, and missing values are discussed. The superior performance and usefulness of the proposed algorithm over the classical random forests method are illustrated via synthetic and real cases, where the remotely sensed geophysical covariates in North West Minerals Province of Queensland, Australia, are used as input spatial data for geology mapping, geochemical prediction, and process discovery analysis

We report the observation of a two-dimensional (2D) checkerboard charge density wave (CDW) in the low-dimensional superconductor Ta₄Pd₃Te₁₆. By determining its CDW properties across the temperature-pressure (T−P) phase diagram and comparing with prototypical CDW materials, we conclude that Ta₄Pd₃Te₁₆ features (a) an incommensurate CDW with a mixed character of dimensions [quasi-1D (Q1D) considering its needlelike shape along the b axis, Q2D as the CDW has checkerboard wave vectors, and 3D because of CDW projections along all three axes], and (b) one of the weakest CDWs compared to its superconductivity (SC), i.e., enhanced SC with respect to CDW, suggesting an interesting interplay of the two orders.

Relativistic transparency enables volumetric laser interaction with overdense plasmas and direct laser acceleration of electrons to relativistic velocities. The dense electron current generates a magnetic filament with field strength of the order of the laser amplitude (>10⁵ T). The magnetic filament traps the electrons radially, enabling efficient acceleration and conversion of laser energy into MeV photons by electron oscillations in the filament. The use of microstructured targets stabilizes the hosing instabilities associated with relativistically transparent interactions, resulting in robust and repeatable production of this phenomenon. Analytical scaling laws are derived to describe the radiated photon spectrum and energy from the magnetic filament phenomenon in terms of the laser intensity, focal radius, pulse duration, and the plasma density. These scaling laws are compared to 3D particle-in-cell (PIC) simulations, demonstrating agreement over two regimes of focal radius. Preliminary experiments to study this phenomenon at moderate intensity (a₀ ∼ 30) were performed on the Texas Petawatt Laser. Experimental signatures of the magnetic filament phenomenon are observed in the electron and photon spectra recorded in a subset of these experiments that is consistent with the experimental design, analytical scaling and 3D PIC simulations. Implications for future experimental campaigns are discussed.

We present experiments directly demonstrating the significance of charge-state dynamics in close collisions at ion velocities below the Bohr velocity resulting in a drastic trajectory dependence of the specific energy loss.
Experiments were performed with the time-of-flight medium energy ion scattering set-up at Uppsala University [1]. In our 3D-transmission approach [2], pulsed beams of singly charged ions are transmitted through self-supporting Si(100) nanomembranes and detected behind the sample. We record ion energy together with the angular distributions of deflected particles and can additionally insert a deflector to measure exit charge states [3].
We specifically studied the difference in energy loss between channelled (ΔEch) and random trajectories (ΔEr) for ions with masses ranging from 1 (protons) to 40 u (Ar+) as shown in Fig. 1 [4,5]. For protons, the observed effect can be explained with increasing contributions of core-electron excitations in close collisions only attainable in random geometry. For He and heavier ions we observe a reverse trend – a decrease of the ratio ΔEch/ ΔEr with decreasing ion velocity. Due to the inefficiency of core-electron excitations at these velocities, we explain this behaviour by contributions of collision-induced charge-exchange events along random trajectories. The resulting higher mean charge state leads to higher electronic stopping along random trajectories. For heavier ions, local losses due to electron promotion, also including several electrons, are expected to contribute strongly to the energy deposition in random geometry. By studying the trajectory dependence of the statistical distribution of electronic excitations (electronic energy straggling), we present evidence that for heavier ions, individual events with large energy transfer indeed significantly contribute to the energy loss. Finally, we show that our experimental approach leads to results that can serve to benchmark dynamic theories such as time-dependent density functional theory [5].

References
[1] M. A. Sortica et al., Nucl. Instrum. Methods Phys. Res. B 463 (2020) 16-20.
[2] R. Holeňák, S. Lohmann and D. Primetzhofer, Ultramicroscopy 217 (2020) 113051.
[3] R. Holeňák et al., Vacuum 185 (2021) 109988.
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[5] S. Lohmann, R. Holeňák and D. Primetzhofer, Phys. Rev. A 102 (2020) 062803.

An acidophilic consortium leached over 70% of the total Zn, As, Co and Cd contents of a tailing and waste rock samples obtained from Neves Corvo mine, Portugal. Also, about 20 and 50 % of the total Cu and Mn contents of the sulfidic mine wastes were also leached by the consortium.

The bioleaching of metals (Pb, Ag and In) by marine sulfur-oxidising bacteria was improved after microwave roasting of a waste rock sample at 400 and/or 500°C. The bioleaching of Pb, Ag and In was increased from 20, 6 and 0 % (before microwave roasting) to 63, 37 and 27 % after microwave roasting.

The global demand for various metals has greatly increased over the past few years and this demand is envisaged to double over the next coming decades. The extractive waste residue (tailings) by the EU mining industries is a large waste stream and could constitute various environmental hazards such as acid mine drainage, especially when poorly managed. Reprocessing of these tailings could be a significant source of valuable metals and could alleviate environmental risks. This calls for a cost-effective metal mining technology with minimal damaging effect to the environment. We hereby propose the use of (halo)alkaliphilic and/or marine sulfur-oxidizing bacteria that live at neutral to alkaline conditions for the bioleaching of elements from these tailings. This will prevent the acidification of the environment, which is the case when bioleaching with acidophilic bacteria. In addition, this bioleaching approach which could be applicable in seawater is beneficial as fresh water could be saved.

The use of microorganisms and their products for the extraction of metals from low grade ores has proven overtime to be more economically viable than other extractive metallurgical processes such as pyrometallurgy. However, the most extensively studied microorganisms for bioleaching are the acidophilic Sulfur and/or Iron-oxidizing chemolithotrophs that are able to catalyze mineral dissolution at low pH. The use of acidophilic bacteria for bioleaching leads to the acidification of the environment as these activities are usually performed at pH ≤ 2. This could have a negative impact on the environment. We hereby propose the use of (halo)alkaliphilic and/or marine sulphur-oxidising microorganisms that live at less acidic, neutral or alkaline conditions for the bioleaching of metals from mining waste. This will prevent the acidification of the environment and save fresh water, as this bioleaching approach could be applicable in seawater. Bioleaching results with Thioclava electrotropha and Thioclava pacifica autotrophs seem promising, as up to 30% Co and 10% Cu, Pb, Zn, Cd, As, K and Mn were solubilised from a fresh waste rock sample. To optimize the bioleaching process, the interaction of these microorganisms with minerals will be studied. The tailing residues cleaned via this approach will be analyzed for subsequent valorization into various circular-economy applications such as inorganic polymers, green cements and ceramics.

Proton capture on the excited isomeric state of 26Al strongly influences the abundance of 26Mg ejected in explosive astronomical events and, as such, plays a critical role in determining the initial content of radiogenic 26Al in presolar grains. This reaction also affects the temperature range for thermal equilibrium between the ground and isomeric levels. We present a novel technique, which exploits the isospin symmetry of the nuclear force, to address the long-standing challenge of determining proton-capture rates on excited nuclear levels. Such a technique has in-built tests that strongly support its veracity and, for the first time, we have experimentally constrained the strengths of resonances that dominate the astrophysical 26mAl(p,γ)27Si reaction. These constraints demonstrate that the rate is at least a factor ∼8 lower than previously expected, indicating an increase in the stellar production of 26Mg and a possible need to reinvestigate sensitivity studies involving the thermal equilibration of 26Al.

Statusreport SiPM readout for NeuLAND (saturation effects, dark rate and time resolution measurements)

Ein Multipixel-Photodetektor weist elektrisch parallel geschaltete erste Avalanche-Photodioden mit jeweils einer Lichteintrittsfläche und elektrisch parallel geschaltete zweite Avalanche-Photodioden mit jeweils einer Lichteintrittsfläche auf. Die Lichteintrittsfläche jeder ersten Avalanche-Photodiode ist gleich oder größer einer Referenzfläche. Die Lichteintrittsfläche jeder zweiten Avalanche-Photodiode ist kleiner als die Referenzfläche. Die Lichteintrittsflächen der ersten und zweiten Avalanche-Photodioden bilden Teilflächen eines Belichtungsfeldes des Multipixel-Photodetektors.

es hat keine aussagefähiges Abstract vorgelegen

es hat keine aussagefähiges Abstract vorgelegen

The year 2021 was still overshadowed by waves of the COVID-19 pandemic, although the arrival of efficient vaccinations together with the experience of the preceding year gave us a certain routine in handling the situation. By now the execution of meetings in an online mode using zoom and similar video conference systems has been recognized as actually being useful in certain situations, e.g. instead of flying across Europe to attend a three-hours meeting, but also to be able to attend seminars of distinguished scientists which otherwise would not be easily accessible.
The scientific productivity of the institute has remained on a very high level, counting 190 publications with an unprecedented average impact factor of 8.0. Six outstanding and representative publications are reprinted in this Annual Report. 16 new third-party projects were granted, among them 7 DFG projects, but very remarkably also an EU funded project on nonlinear magnons for reservoir computing with industrial participation of Infineon Technologies Dresden and GlobalFoundries Dresden coordinated by Kathrin Schultheiß of our Institute.
The scientific success was also reflected in two HZDR prizes awarded to the members of the Institute: Dr. Katrin Schultheiß received the HZDR Forschungspreis for her work on “Nonlinear magnonics as basis for a spin based neuromorphic computing architecture”, and Dr. Toni Hache was awarded the Doktorandenpreis for his thesis entitled “Frequency control of auto-oscillations of the magnetization in spin Hall nano-oscillators”. Our highly successful theoretician Dr. Arkady Krasheninnikov was quoted as Highly Cited Researcher 2021 by Clarivate.
The new 1-MV facility for accelerator mass spectrometry (AMS) has been ordered from NEC (National Electrostatics Corporation). Design of a dedicated building to house the accelerator, the SIMS and including additional chemistry laboratories for enhanced sample preparation capabilities has started and construction is planned to be finished by mid 2023, when the majority of the AMS components are scheduled for delivery.
In the course of developing a strategy for the HZDR - HZDR 2030+ Moving Research to the NEXT Level for the NEXT Gens - six research focus areas for our institute were identified.
Concerning personalia, it should be mentioned that the long-time head of the spectroscopy department PD Dr. Harald Schneider went into retirement. His successor is Dr. Stephan Winnerl, who has been a key scientist in this department already for two decades. In addition, PD Dr. Sebastian Fähler was hired in the magnetism department who transferred several third-party projects with the associated PhD students to the Institute and strengthens our ties to the High Magnetic Field Laboratory, but also to the Institute of Fluid Dynamics.
Finally, we would like to cordially thank all partners, friends, and organizations who supported our progress in 2021. First and foremost we thank the Executive Board of the Helmholtz-Zentrum Dresden-Rossendorf, the Minister of Science and Arts of the Free State of Saxony, and the Ministers of Education and Research, and of Economic Affairs and Climate Action of the Federal Government of Germany. Many partners from universities, industry and research institutes all around the world contributed essentially, and play a crucial role for the further development of the institute. Last but not least, the directors would like to thank all members of our institute for their efforts in these very special times and excellent contributions in 2021.

Ion-Laser InterAction Mass Spectrometry (ILIAMS) slows down anions to thermal kinetic energies in a radiofrequency quadrupole (RFQ) filled with He buffer gas. Laser light (e.g. 532 nm) is overlapped with the
decelerated anions to separate isobars via photodetachment.
Here, we present two applications of ILIAMS at the 3MV Vienna Environmental Research Accelerator (VERA): 26Al is an established AMS nuclide but its detection can be improved using AlO−, which is formed more likely than the customarily applied Al−. ILIAMS suppresses the isobar 26Mg by neutralization of MgO− and overcomes the disadvantage of AlO− compared to Al−, where Mg− is not extracted from the ion source. This enhances the sensitivity of 26Al detection and the prolific AlO− beam can be used at facilities with terminal voltages
<10 MV. 135,137Cs measurements are presented as an example of highly sensitive detection of novel AMS nuclides. In this case, we use 135,137CsF2− anions and ILIAMS suppresses the isobaric 135,137BaF− .
We furthermore present a new design of a modular ion cooler with multiple RFQ sections. With more control of the ion energy during their passage through the RFQ we want to improve the transport efficiency for molecular anions. This ion cooler will be integrated in a new 1MV AMS facility at Dresden in 2023.

In the Jakupica Mt. (North Macedonia, Central Balkan Peninsula; ~41.7° N, ~21.4 E; maximum elevation: 2540 m asl) a large plateau glacier was reconstructed. The lowest mapped moraines in the northeastern valleys are at elevations of 1490-1720 m asl and suggest the former existence of glacier tongues of ~3 km length. The maximum ice extent and five deglaciation phases were reconstructed. The equilibrium line altitude (ELA) of the most extended glacial phase is 2073+37/-25 m asl. The 10Be Cosmic Ray Exposure (CRE) age (n=8) of this phase was estimated at 19.3+1.7/-1.3 ka, conformable with the LGM similarly to the nearby Jablanica Mt [1]. CRE ages from the next moraine generation placed the first phase of deglaciation to 18.2+1.0/-3.0 ka (n=8). The samples from the moraine of the penultimate deglaciation phase (n=5) provided CRE ages with large scatter and
biased towards old ages, which is probably the result of inherited cosmogenic nuclide concentrations within the rock [2, 3], as it was suggested in the cirques of the Retezat Mt. [4].
Glacio-climatological modelling was performed under constrains of geomorphological evidence in order to make paleoclimatological inferences. The degree-day model was used to calculate the amount of accumulation required to sustain the glaciological equilibrium assuming a certain temperature drop at the ELA for the most extended stage.
If the LGM mean annual temperature and the increased annual temperature range suggested by pollen-based paleoclimate reconstructions [5] are placed into the glaciological model the estimated annual total melt at the LGM ELA implies much wetter conditions compared to the current climate. This is in contrast with the regional LGM annual precipitation reconstructions of the same dataset, which suggests ~25% decrease in the Jakupica Mt. Alternatively, the model can be constrained with the current annual temperature range and the regional estimates of LGM temperature drop at 6-7 °C. This suggests 1.3 to 1.8 times more simulated precipitation than
today.
These results support paleoclimate models, which predict increased precipitation in this region and suggest that in the Central Balkan region either the precipitation or the annual temperature amplitude (or both) are inaccurate in the pollen-based paleoclimate reconstruction database.

Funding: NKFIH FK124807; GINOP-2.3.2-15-2016-00009; RADIATE 19001688-ST.
[1] Ruszkiczay-Rüdiger et al. 2020. Geomorphology 351: 106985
[2] Ruszkiczay-Rüdiger et al. 2021. GRA, EGU21-4573
[3] Ruszkiczay-Rüdiger et al. 2021. vDEUQUA2021, Book of Abstracts, DOI: 10.5281/zenodo.5526214
[4] Ruszkiczay-Rüdiger et al. 2021. Geomorphology, 107719.
[5] Bartlein, et al. 2011. Clim. Dyn. 37, 775–802.

es hat keine aussagefähiges Abstract vorgelegen

Creation of electrons and positrons from light alone is a basic prediction of quantum electrodynamics, but yet to be observed. Our simulations show that the required conditions are achievable using a high-intensity two-beam laser facility and an advanced target design. Dual laser irradiation of a structured target produces high-density gamma rays that then create > 10(8) positrons at intensities of 2 x 10(22) Wcm(-2). The unique feature of this setup is that the pair creation is primarily driven by the linear Breit-Wheeler process (gamma gamma -> e(+)e(-)), which dominates over the nonlinear Breit-Wheeler and Bethe-Heitler processes. The favorable scaling with laser intensity of the linear process prompts reconsideration of its neglect in simulation studies and also permits positron jet formation at experimentally feasible intensities. Simulations show that the positrons, confined by a quasistatic plasma magnetic field, may be accelerated by the lasers to energies >200 MeV.

es hat keine aussagefähiges Abstract vorgelegen

Contactless inductive flow tomography (CIFT) can reconstruct the global 3D flow field in liquid metals. The technique is based on measuring very small magnetic fields induced by currents in the conducting liquid arising from the fluid motion under the influence of two primary excitation fields and solving the according linear inverse problem [1]. We present experimental results of CIFT measurements on a large cylindrical vessel with a height of 640 mm and a diameter of 320 mm, i.e. aspect ratio 0.5, filled with the eutectic alloy GaInSn. The liquid metal is heated from the bottom and cooled from the top, i.e. a so-called Rayleigh-Bénard (RB) convection cell. The temperature gradient drives a complex flow, that varies spatially and temporally [2-5].
The experimental set-up includes a number of Fluxgate sensors for highly sensitive measurements of the induced magnetic field in the order of 10 nT [6] as well as Ultrasound-Doppler velocimetry probes, that directly measure the velocity of the flow along their line-of-sight. Our preliminary measurements used only the excitation field in vertical direction, yet show a very high agreement of the time-dependent velocity profiles measured by UDV and the according CIFT data, projected onto the line-of-sight of the UDV sensors.

Acknowledgement
This work was supported by the German Research Foundation (DFG) under project no. 374994652. T.V. and F.S. also thank the DFG for support under the grant VO 2331/1.

REFERENCES
[1] Stefani F., Gundrum T., Gerbeth G., Physical Review E 70: 056306. 2004.
[2] Akashi M. et al., J. Fluid Mech. 932 (2022).
[3] Zürner T. et al., J. Fluid Mech. 876 (2019).
[4] Vogt T. et al., PNAS 115 (2018).
[5] Mitra R. et al., Magnetohydrodynamics, vol. 58 (2022) [accepted for publication].
[6] Sieger M. et al., Magnetohydrodynamics, vol. 58 (2022) [accepted for publication].

es hat kein aussagefähiges Abstract vorgelegen

Mine waste can constitute environmental hazards, especially when poorly managed. Environmental assessment is essential for estimating potential threats and optimizing mine waste management. This study evaluated a potential environmental risk of sulfidic mine waste samples originating from the Neves Corvo Mine, Portugal and the closed Freiberg mining district, Germany. Metal(loid)s in the waste samples were partitioned into seven operationally defined fractions using the Zeien and Brummer sequential extraction scheme. Results showed similar partitioning patterns for the elements in the waste rock and tailing samples from Neves Corvo Mine; most metal(loid)s showed lower mobility as they were mainly residual-bound. On the contrary, the Freiberg tailing had considerably elevated (24-37%) mobile fractions of Zn, Co, Cd and Mn. The majority of Fe (83-96%) in all samples was retained in the residual fractions, while Ca was highly mobile. Overall, Pb was the most mobile toxic element in the three samples. A large portion of Pb (32-57%) was predominantly found in the most mobilizable fractions of the studied waste samples. This study revealed that the three mine wastes have a contamination potential for Pb, which can be easily released into the environment from these wastes.

The daily clinical practice in Nuclear Medicine makes use of radiopharmaceuticals that either are obtained from
external commercial suppliers or prepared in-house for immediate use. The latter are usually non-commercial
preparations that represent the major source of radiopharmaceuticals for essential routine Nuclear Medicine
practices for both diagnostic and therapeutic applications. According to European legislation, namely directive
2001/83/EC, radiopharmaceuticals that are commercially distributed must have a marketing authorization (MA)
to be placed on the market. The availability of this type of finished radiopharmaceutical products with MA ready
to use is limited due to different reasons: one is the very short half-life or shelf life, which limits the shipment of
these radiopharmaceuticals from external sources. In addition, the market potential for radiopharmaceuticals that
are used in rare clinical indications is limited to be financially attractive for pharmaceutical industry, and therefore
the number of MA applications for radiopharmaceuticals is concise.
However, the development of innovative radiopharmaceuticals usually takes place in radiopharmacies, research
centres or nuclear medicine laboratories. Practically all recent major clinical breakthroughs in Nuclear Medicine
over the last decade, exemplified by the success of theranostics with Somatostatin analogs and prostate cancer
applications, were based on the use of in-house preparations of these innovative products. In case a new
radiopharmaceutical has both the technical (half-life) and clinical potential to be produced and distributed
commercially, these new radiopharmaceuticals more frequently make their way to pharmaceutical companies that
take over from academia and provide funding for further clinical trials besides phase 0 / phase I.
European legislation treats radiopharmaceuticals used in the preparation process of a radiopharmaceutical different
than other, i.e., non-radioactive pharmaceuticals, by requiring a marketing authorization not only for ready to use
radiopharmaceuticals that are to be placed on the market but as well for starting materials such as radionuclide
generators, radionuclide precursors and kits. To avoid misunderstanding, we shall refer throughout the remainder
of this document to the term “licensed” for starting materials with a MA.
This document describes the EANM commitment and support to the non-commercial in-house preparation of
radiopharmaceuticals for direct use in compliance with European and national regulations, including the
“compounding” using licensed starting materials (with MA) such as kits, radionuclide generators or radionuclide
precursors, as well as the preparation of diagnostic (PET and SPECT) and therapeutic radiopharmaceuticals using
more complex methods and usually unlicensed starting materials (without MA). Starting point for
recommendations have been laid down in the guidelines as described in the current Good Radiopharmaceutical
Practice (cGRPP).

Autonomous computational frameworks such as AFLOW are generating large databases that
power materials discovery workflows. The AFLOW.org repository is the largest of its kind,
containing more than 3 million compounds each characterized by 180+ different properties. The
data has been employed for the discovery of two magnets – the first discovered by computational
approaches – and six new high-entropy, high-hardness metal carbides. Join us for an online weeklong
hands-on workshop on AFLOW. Topics covered include database structure and generation,
structure prototypes and crystal symmetry, thermal and elastic properties analysis, thermodynamic
stability analysis, and integration of machine learning models for property prediction and
descriptor development.

Materials databases such as AFLOW [1] leverage ab initio calculations
for autonomous materials design. The predictive power critically relies
on accurate formation enthalpies - quantifying the thermodynamic
stability of a system. For ionic materials such as oxides and nitrides,
standard DFT leads to errors of several hundred meV/atom [2,3].
We have recently developed the "coordination corrected enthalpies"
(CCE) method yielding highly accurate room temperature formation
enthalpies with mean absolute errors down to 27 meV/atom [3]. Here,
we introduce AFLOW-CCE [4]: a tool where users can input a structure
file and receive the CCE corrections, or even the CCE formation
enthalpies if pre-calculated LDA, PBE or SCAN values are provided.
The results can be used for the design of e.g. 2D materials.
[1] S. Curtarolo et al., Comput. Mater. Sci. 58, 218 (2012).
[2] V. Stevanović et al., Phys. Rev. B 85, 115104 (2012).
[3] R. Friedrich et al., npj Comput. Mater. 5, 59 (2019).
[4] R. Friedrich et al., Phys. Rev. Mater. 5, 043803 (2021).

Materials discovery and design critically relies on accurate enthalpies. The formation
enthalpy – quantifying the thermodynamic stability of a compound – is a key quantity
in ab initio materials databases such as AFLOW [1] to enable autonomous materials
design. For ionic systems such as chalcogenides (e.g. oxides), pnictides (e.g.
nitrides), and halides, standard semi-local DFT leads, however, to errors of several
hundred meV/atom [2,3] for this quantity inhibiting materials design.
To address this critical issue, we have developed the "coordination corrected
enthalpies" (CCE) method yielding highly accurate room temperature formation
enthalpies with mean absolute errors down to 27 meV/atom [3]. Recently, we have
also introduced AFLOW-CCE [4]: an implementation of the method into the freely
available AFLOW software for automated correction of DFT results. The tool returns
the CCE corrections, or even the CCE formation enthalpies if pre-calculated LDA, PBE
or SCAN values are provided. The autonomous implementation enables the enthalpy
correction of an extensive library of materials as well as the accurate and quick
generation of convex hull phase diagrams. The results can also be used for the
computational design of e.g. nanoscale materials [5].
[1] S. Curtarolo et al., Comput. Mater. Sci. 58, 218 (2012).
[2] V. Stevanović et al., Phys. Rev. B 85, 115104 (2012).
[3] R. Friedrich et al., npj Comput. Mater. 5, 59 (2019).
[4] R. Friedrich et al., Phys. Rev. Mater. 5, 043803 (2021).
[5] R. Friedrich et al., in preparation (2021).

Nanomagnets of complex geometrical shape and nanosized characteristic scales are hardly accessible via conventional solutions for numerical modelling. In the meantime, they are of high fundamental and applied interest, showing a novel interplay between geometry and magnetic sublattice. Recent advances in fabrication and characterization of curvilinear magnets hold an additional interest to them and force the further development of analytical and numerical tools to address such systems at the large scale. The latter include a flexible user interface to describe the concrete problem, and parallel computing to handle billions of degrees of freedom. Here, we will overview the present approaches to design spin-lattice and micromagnetic solvers based on the Landau-Lifshitz equation and discuss our experience in the software engineering of these tools.

In comparison with ferromagnetic domain walls and skyrmions, their coun-
terparts in antiferromagnets (AFMs) demonstrate appealing properties in
their control and dynamics, e.g., absence of Walker limit and Magnus force
[1]. The complex intrinsic magnetic structure of AFMs leads to special prop-
erties such as negligibly small stray fields, exchange-enhanced resonance
frequencies up to THz range, and the presence of staggered spin-orbit torques.
Together they render AFMs as prospective materials for spintronic and
spin-orbitronic applications [2]. Here, we consider bipartite, easy-axis AFM
samples of finite size. We derive the boundary conditions for the Neel order
parameter in the presence of Dzyaloshinskii-Moriya interactions (DMI) of
Bloch type in addition to exchange (see Fig. 1), and apply them to describe
domain walls and skyrmions. DMI leads to the deformation of the uniform
ground state at the side faces, with the twist angle proportional to the DMI
coefficient. Both domain walls and skyrmions become wider and change
their type to the mixed Bloch-Neel one when approaching the top (bottom)
surface of the sample. The characteristic depth where the influence of the
boundary on magnetic texture is significant is about 5 magnetic lengths [3].
In the absence of the intrinsic DMI, the exchange-driven boundary conditions
determine the behavior of domain walls in AFMs with a patterned surface.
Imaging the domain wall in a single crystal Cr 2O3 using nitrogen vacancy
(NV) magnetometry, we show that it mimics the behavior of an elastic
ribbon deformed by the effective pinning sites created by mesas. Crossing
the mesa at an angle, the domain wall shape experiences an additional bend, determined by the aspect ratio of the mesa A=t/w with t and w being
its thickness and width, see Fig. 2. This deformation can be described by the
effective Snell’s law as sin θi/sin θr ≈ 1 + 3.1 A with θi and θr being incidence
and refraction angles at the top surface [4].
[1] O. Gomonay, V. Baltz, A. Brataas et al. Nat. Phys. Vol. 14, P. 213
(2018). [2] V. Baltz, A. Manchon, M. Tsoi etal. Rev. Mod. Phys. Vol. 90, P.
015005 (2018), H. Yan, Z. Feng, P. Qin etal. Avd. Mat. Vol. 32, P. 1905603
(2020). [3] O. V. Pylypovskyi, A. V. Tomilo, D. D. Sheka et al. Phys. Rev.
B, Vol. 103, P. 134413 (2021) [4] N. Hedrich, K. Wagner, O. V. Pyly-
povskyi et al. Nat. Phys. Vol. 17, P. 574 (2021)

A complex structure of magnetic subsystem in antiferromagnets (AFMs) determines challenges and technological perspectives for both, fundamental
research and their applications for spintronic and spin-orbitronic devices [1]. In this respect, properties of the confined samples are of key interest because
of the possibility to tune magnetic responses via effects of boundary and geometrical curvature [2]. Here, we consider textures in (i) AFM slabs with the
Dzyaloshniskii-Morya interaction (DMI) of bulk symmetry [3] and (ii) the intrinsically achiral curvilinear spin chains arranged along space curves [4].
We derive a transition from spin lattice of G-type AFM to the sigma-model with the respective boundary conditions for the AFM order parameter [3]. The
DMI influences a texture via boundary conditions modifying the ground state, domain wall shape and skyrmion profiles. Approaching the boundary in the
slab with easy-axis anisotropy, the domain wall becomes broader and of mixed Bloch-Neel type near the top surface. Near the edges of the sample, the
domain wall plane possesses and additional twist. Note, that the edge twists appear in achiral AFMs as well if the domain wall plane lies at an angle to the
side faces [5]. Similarly, skyrmions of any radius become of the Bloch-Neel type approaching the top/bottom surfaces of the sample. The radius of narrow
skyrmions changes up to 10% due to the boundary effects.
AFM spin chains arranged along space curves can model the simplest curvilinear nanoarchitectures. Their geometry is described by the curvature and
torsion, determining local bends and twists of the curve. The geometry-driven anisotropy and inhomogeneous DMI render them as chiral helimagnets [6].
In addition, the exchange interaction generates the weakly ferromagnetic response, scaling linearly with curvature and torsion. The inter- and single-ion
anisotropies in curvilinear AFM chains lead to the additional anisotropic contributions, scaling with curvature. The single-ion anisotropy leads to the
homogeneous DMI mixing normal and tangential components of ferro- and antiferromagnetic vector order parameters. Both anisotropy models contribute
to the additional easy axes, which determine the direction of the order parameters in spin-flop phase [4].
[1] V. Baltz et al, Rev. Mod. Phys. 90, 015005 (2018); A. Manchon et al, Rev. Mod. Phys. 91, 035004 (2019)
[2] P. Fischer et al, APL Mat. 8, 010701 (2020); R. Streubel et al, J. Appl. Phys. 129, 210902 (2021); D. D. Sheka, Appl. Phys. Lett. 118, 230502 (2021)
[3] O. V. Pylypovskyi et al, Phys. Rev. B 103, 134413 (2021)
[4] O. V. Pylypovskyi et al, Appl. Phys. Lett. 118, 182405 (2021)
[5] N. Hedrich et al, Nat. Phys. 17, 574 (2021)
[6] O. V. Pylypovskyi, D. Y. Kononenko et al, Nano Lett. 20, 8157 (2020)

We draw a parallel between ferromagnetic materials and nematic liquid crystals
confined on curved surfaces, which are both characterized by local interaction and
anchoring potentials. We show that the extrinsic curvature of the shell combined with
the out-of-plane component of the director field gives rise to chirality effects. This
interplay produces an effective energy term reminiscent of the chiral term in
cholesteric liquid crystals, with the curvature tensor acting as a sort of anisotropic
helicity. We discuss also how the different nature of the order parameter, a vector in
ferromagnets and a tensor in nematics, yields different textures on surfaces with
the same topology as the sphere.

The behaviour of any physical system is governed by the order parameter,
determined by the geometry of the physical space of the object, namely their
dimensionality and curvature. Usually, the effects of curvature are described
using local interactions only, e.g. local spin-orbit- or curvature-induced
Rashba and Dzyaloshinskii-Moriya interactions (DMI). In the specific case
of ferromagnetism, until recently, there was no analytical framework, which
was treating curvature effects stemming from local [1] and non-local [2]
interactions on the same footing. The lack of a proper theoretical foundation
impedes the description of essential micromagnetic textures like magnetic
domains, skyrmion-bubbles and vortices. Here, we present a micromag-
netic theory of curvilinear ferromagnetic shells, which allows to describe the
geometry-driven effects stemming from exchange and magnetostatics within
the same framework [3]. A general description of magnetic curvilinear shells
can be done using tangential derivatives of the unit magnetization vector.
Tangential derivatives are represented by the covariant derivatives of in-
surface components and the regular derivative of the normal magnetiza-
tion component, normalized by the square root of the corresponding metric
tensor coefficient. This allows to separate the explicit effects of curvature
and spurious effects of the reference frame. The shape of a given thin shell
can be determined by two principal curvatures k1 and k2, which are functions
of coordinate. The respective classification of curvilinear surfaces operates
with (i) developable surfaces, where one of the principal curvatures equals
to zero; (ii) minimal ones, where the mean curvature k1 + k2 = 0; and (iii)
the general case. The local geometry-driven energy contributions are repre-
sented by the DMI and anisotropy, whose coefficients are determined by
powers of the principal curvatures. This allows to cancel the influence of one
of the DMI terms for the developable surfaces for any magnetic texture. The
magnetostatic interaction is a source of new chiral effects, which are essen-
tially non-local in contrast to the conventional DMI. The physical origin is
the non-zero mean curvature of a shell and the non-equivalence between the
top and bottom surfaces of the shell. We demonstrate that the analysis of
non-local effects in curvilinear thin shells can become more straightforward
when introducing three magnetostatic charges. In this respect, in contrast
to the classical approach by Brown [4], we split a conventional volume
magnetostatic charge into two terms: (i) magnetostatic charge, governed by
the tangent to the sample’s surface, and (ii) geometrical charge, given by the
normal component of magnetization and the mean curvature. In addition to
the shape anisotropy (local effect), there appear four additional non-local
terms, determined by the surface curvature. Three of them are zero for any
magnetic texture in shells with the geometry of minimal surfaces. The fourth
term is determined by the non-equivalence of the top and bottom surfaces
of the shell and becomes zero only for the special symmetries of magnetic
textures. The discovered non-local magnetochiral effects introduce hand-
edness in an intrinsically achiral material and enables the design of magne-
to-electric and ferro-toroidic responses. This will stimulate to rethink the
origin of chiral effects in different systems, e.g. in fundamentally appealing
and technologically relevant skyrmionic systems, and further theoretical
investigations in the field of curvilinear magnetism as well as experimental
validation of these theoretical predictions. These developments will pave the
way towards new device ideas relying on curvature effects in magnetic nano-
structures. The impact of effects predicted in this work goes well beyond
the magnetism community. Our description of the vector field behaviour
can be applied to different emergent field of studies of curvature effects.
The prospective applications include curved superconductors [5], twisted
graphene bilayers [6], flexible ferroelectrics [7], curved liquid crystals [8].

[1] Yu. Gaididei, V. P. Kravchuk, D. D. Sheka, Phys. Rev. Lett., 112,
257203 (2014); D. D. Sheka, V. P. Kravchuk, Yu. Gaididei, J. Phys. A:
Math. Theor., 48, 125202 (2015); O. V. Pylypovskyi, V. P. Kravchuk,
D. D. Sheka et al, Phys. Rev. Lett., 114, 197204 (2015); V. P. Kravchuk,
D. D. Sheka, A. Kakay et al, Phys. Rev. Lett., 120, 067201 (2018) [2] P.
Landeros, A. S. Nunez, J. Appl. Phys. Vol. 108, p. 033917 (2010); J. A.
Otalora, M. Yan, H. Schultheiss et al, Phys. Rev. Lett., 117, 227203 (2016);
J. A. Otalora, M. Yan, H. Schultheiss et al, Phys. Rev. B, 95, 184415 (2017)
[3] D. D. Sheka, O. V. Pylypovskyi, P. Landeros et al., Comm. Phys. 3, 128
(2020) [4] W. F. Brown Jr. Micromagnetics (Wiley, New York, 1963) [5]
V. Vitelly, A. M. Turner, Phys. Rev. Lett., 93, 215301 (2004) [6] W. Yan,
W.-Y. He, Z.-D. Chu et al, Nat. Comm., 4, 2159 (2013) [7] M. Owczarek, K.
A. Hujsak, D. P. Ferris et al, Nat. Comm., 7, 13108 (2016) [8] G. Napoli, L.
Vergori, Phys. Rev. Lett., 108, 207803 (2012)

The cannabinoid receptor type 2 (CB2R) is an attractive target for diagnosis and therapy of neurodegenerative diseases and cancer. Recently, we reported a novel naphthyrid-2-one based positron-emission tomography (PET) radioligand for imaging of the CB2R in the brain ([18F]5). In this study we aimed at the development of a novel 18F-labeled CB2R radioligand with improved binding properties and metabolic stability. Starting from the structure of 5, we developed a novel series of fluorinated derivatives by modifying the substituents at the naphthyrid-2-one subunit. Compound 28 (LU13) was identified with the highest binding affinity and selectivity versus CB1R (CB2RKi = 0.6 nM; CB1RKi/CB2RKi > 1000) and was selected for radiolabeling with 18F and biological characterization. The radiofluorination was performed starting from the corresponding bromo-precursor (31) bearing a fully deuterated N-alkyl chain to protect against defluorination. The in vitro evaluation of [18F]LU13 proved the high binding affinity of the radioligand towards rat (rCB2RKD = 0.2 nM) and human (hCB2RKD = 1.1 nM) CB2R. Metabolism studies in mice revealed a metabolic stability at 30 min p.i. with fractions of parent compound of >80% in the brain and 90% in the spleen with only trace of defluorination products detected in plasma. PET imaging in a rat model of vector-based/related overexpression in the striatum revealed a high signal to background ratio, demonstrating the ability of [18F]LU13 to reach and selectively label the hCB2R in the brain. Thus, [18F]LU13 is a novel and highly promising PET radioligand for the imaging of up regulated CB2R expression under pathological conditions in the brain.

The Sakatti Ni-Cu-platinum-group element deposit is situated in northern Finland and comprises massive, disseminated, and
vein sulfide mineralization. A stockwork is formed by chalcopyrite-rich sulfide veins, which contain exceptionally high
platinum-group elements and Au grades. The mineralogy and geochemistry of this stockwork zone ore is documented in this
investigation. The results are used to develop the first robust genetic concept and its relationship to massive and
disseminated mineralization of the Sakatti deposit. This model is similar to that proposed for many Cu-rich magmatic sulfide
ores, most importantly the Cu-rich footwall veins described from the Sudbury Complex in Canada and the Cu-rich ore at
Noril’sk-Talnakh in Russia. Detailed petrographic studies using a sample suite from exploration drill core intersecting veinstyle
mineralization revealed a classic magmatic sulfide assemblage of chalcopyrite 6 pyrrhotite, pentlandite, and pyrite.
More than 1000 platinum-group mineral grains belonging almost exclusively to the moncheite (PtTe2) – merenskyite (PdTe2)
– melonite (NiTe2) solid solution series were identified in the studied samples. Notably, almost two thirds of the platinumgroup
element-bearing minerals consist of melonite. Some of the platinum-group minerals contain inclusions of Ag-rich gold
(AgAu2) and muthmannite (AuAgTe2). Most of the platinum-group minerals occur as inclusions in chalcopyrite, although a
few grains are located at base-metal sulfide grain boundaries and in fractures in base-metal sulfides. The whole-rock
compositions of the stockwork veins are Cu-rich and are interpreted to represent a fractionated Cu-rich sulfide liquid
enriched in Pt, Pd, Au, Ag, As, Bi, Pb, Se, Te, Zn, which separated from a monosulfide solid solution (mss). An intermediate
solid solution (iss) solidified from the Cu-rich sulfide liquid, recrystallizing chalcopyrite at,550 8C. Simultaneously, small
volumes of intercumulus residual melt contained mainly the precious metals, Bi, and Te due to their incompatibility in iss.
Solitary and composite platinum-group minerals as well as Au-minerals crystallized first from the residual melt (,600 8C),
followed by a succession of various Bi-, Ag-, and Pb-tellurides (~540 8C), and finally sphalerite and galena. Melonite
crystallized as mostly large, solitary grains exsolved directly from Ni-bearing intermediate solid solution (~600 C), shortly
after the formation of moncheite and merenskyite from the residual melt. Finally, remobilization of the platinum-group
minerals occurred at temperatures of,300 C, as suggested by the presence of minor amounts of Cl-bearing minerals and
ragged grain shapes. © 2021 Mineralogical Association of Canada. All rights reserved.

Ion intercalation of perovskite oxides in liquid electrolytes is a very promising method for controlling their functional properties while storing charge, which opens the potential application in different energy and information technologies. Although the role of defect chemistry in the oxygen intercalation in a gaseous environment is well established, the mechanism of ion intercalation in liquid electrolytes at room temperature is poorly understood. In this study, the defect chemistry during ion intercalation of La0.5Sr0.5FeO3-δ thin films in alkaline electrolytes is studied. Oxygen and proton intercalation into the LSF perovskite structure is observed at moderate electrochemical potentials (0.5 V to -0.4 V), giving rise to a change in the oxidation state of Fe (as a charge compensation mechanism). The variation of the concentration of holes as a function of the intercalation potential was characterized by in-situ ellipsometry and the concentration of electron holes was indirectly quantified for different electrochemical potentials. Finally, a dilute defect chemistry model that describes the variation of defect species during ionic intercalation was developed.

The aim of this contribution is to present the necessary vector space structures and transforms
needed for the statistical analysis of multi-way compositions and multivariate distributions. Both
theoretical developments and examples will be provided.
Several contributions to past CoDaWorks and subsequent articles have dealt with two-way
compositions, covering the space structure, the interpretation of its subspaces and ilr coordinates
(e.g.: Egozcue et al., 2008; Fačevicová et al., 2014; de Sousa et al., 2021). This contribution
reviews these results from a common framework and extends towards multivariate distributions.
Multivariate compositions represent joint distributions of multiple categorical variables. They
form vector spaces and are a special case of multivariate Bayes-spaces, containing arbitrary mul-
tivariate distributions. In all these spaces conditional distributions, independent distributions,
and graphical models can be represented by certain subspaces. Appropriate isometric log ratio
representations are constructed from univariate representations. They explicitly separate rele-
vant subspaces related to their dependence structure as described by Markov graphs and the
Hammersley-Clifford theorem.
The contribution shows with three examples how this structural understanding can be used
to apply and interpret classical statistical methods applied to ilr-transformed multi-way compo-
sitions and multivariate distributions:
1. What are the mean and the variance of (observed) conditional distributions? As conditional
distributions are projections in these subspaces, their mean and variance are already well
defined in the projected space.
2. What are relevant hypotheses in linear models with multi-way compositional response? Clas-
sical multivariate linear models can test for the various kinds of dependence representable
by Markov graphs.
3. How to interpret the principal components from datasets of multivariate distributions? The
theory allows to attribute the influence of each PC to perturbations of the marginal distri-
butions and clique interactions.

In the era of big data and internet of things (IoT), information security has emerged as an essential system and application metric. The information exchange among the ubiquitously connected smart electronic devices requires functioning reliably in harsh environments, which highlights the need for securing the hardware root of trust. In this work, by leveraging the uniform nonlinear resistive switching of emerging electroforming-free analog memristive device based on BiFeO3 (BFO) thin film, the security-oriented hardware primitive (SoHP) system is developed and optimized with high-security level. The SoHP system utilizes the distinguishable power conversion efficiency generated at second and higher harmonics in low resistance state (memristor with diodelike behavior) and high resistance state (memristor with high resistive behavior) of memristive devices. By exploring the significant influence of writing bias and operational frequency in sourcing input voltage on the dynamic switching behavior of memristive device, the novel 2-memristor encoding scheme and 1-memristor decoding scheme are developed for SoHP system, which realizes a frequency enhancement of 4000 times in comparison to 1-memristor encoding scheme and 2-memristor decoding scheme. The encoded data bits that generated from physically implemented SoHP system pass diverse statistical test suites (i.e. ENT, BSI, and NIST SP-800.22 statistical test suites), which indicates the high randomness distribution of the encoded data and the high-security level of the proposed memristive encoding system.

The steam‑oxygen gasification process of solid recovered fuel (SRF) was proved as a promising approach for energy and resource sustainability through a comprehensive product analysis. A high content of syngas was produced and suitable for the downstream chemical synthesis and hydrogen energy source. However, tar is a significant hazardous mixture from waste gasification, resulting in low gasification performance and releasing toxic containments. Tar monitoring is thus important. To improve existing tar measurement methods, a flexible tar sampling system (FTSS) and a novel gas chromatography (GC) were developed for off-line and on-line tar monitoring in the pilot-scale gasification process. FTSS is an improvement compared to the standard tar sampling system (STSS) regarding robustness, operation time, and handling. It showed a consistent tar capture performance with STSS. On the other hand, the on-line GC realized real-time tar qualification and quantification. For the gasification at 850 °C, loads of benzene, toluene, and xylene examined by the on-line GC (18.7 g/m3) were highly correspondent to the result from the off-line GC (17.8 g/m3). The carbon fractions of total hydrocarbon tar were also evaluated by the on-line GC with 68 and 25 gC/m3 at the gasification temperatures of 650 and 850 °C, respectively.

In many patients with cancer, the dose of radiation therapy (RT) that can be safely administered is insufficient to achieve high rates of local tumor control and cure. In others, damage to normal tissues is a concern even at moderate doses. In these settings, RT, or chemoradiation therapy (CRT), ideally would be combined with novel targeted drugs that can enhance the tumoricidal effects of standard therapy but without significantly increased normal tissue toxicity.
Over the past decade, major advances in precision medicine have supplied the field of radiation oncology with countless opportunities to enhance the antitumor effects of CRT. However, a large body of preclinical research and clinical investigations on molecular targeted drugs has not yet translated into any meaningful number of combinations of RT or CRT with targeted radiosensitizers that are approved by the US Food and Drug Administration.3 In fact, to date the epidermal growth factors receptor-directed monoclonal antibody cetuximab remains the only targeted agent approved by the Food and Drug Administration for concurrent administration with RT in head and neck (H&N) cancers. There are considerable challenges to clinical translation of combining targeted drugs with CRT or RT that the field has only recently begun to fully appreciate.

The development of molecular targeted drugs with radiation and chemotherapy is critically important for improving the outcomes of patients with hard-to-treat, potentially curable cancers. However, too many preclinical studies have not translated into successful radiation oncology trials. Major contributing factors to this insufficiency include poor reproducibility of preclinical data, inadequate preclinical modeling of intertumoral genomic heterogeneity that influences treatment sensitivity in the clinic, and a reliance on tumor growth delay instead of local control (TCD50) endpoints. There exists an urgent need to overcome these barriers to facilitate successful clinical translation of targeted radiosensitizers. To this end, we have used 3-dimensional (3D) cell culture assays to better model tumor behavior in vivo. Examples of successful prediction of in vivo effects with these 3D assays include radiosensitization of head and neck cancers by inhibiting epidermal growth factor receptor or focal adhesion kinase signaling, and radioresistance associated with oncogenic mutation of KRAS. To address the issue of tumor heterogeneity, we leveraged institutional resources that allow high-throughput 3D screening of radiation combinations with small-molecule inhibitors across genomically characterized cell lines from lung, head and neck, and pancreatic cancers. This high-throughput screen is expected to uncover genomic biomarkers that will inform the successful clinical translation of targeted agents from the National Cancer Institute Cancer Therapy Evaluation Program portfolio and other sources. Screening "hits" need to be subjected to refinement studies that include clonogenic assays, addition of disease-specific chemotherapeutics, target/biomarker validation, and integration of patient-derived tumor models. The chemoradiosensitizing activities of the most promising drugs should be confirmed in TCD50 assays in xenograft models with or without relevant biomarker and using clinically relevant radiation fractionation. We predict that appropriately validated and biomarker-directed targeted therapies will have a higher likelihood than past efforts of being successfully incorporated into the standard management of hard-to-treat tumors.

Purpose: Recurrent tumors (RT) of head and neck squamous cell carcinoma (HNSCC) occur in up to 60%, with poor therapeutic response and detrimental prognosis. We hypothesized that HNSCC RTs successfully evade antitumor immune response and aimed to reveal tumor immune microenvironment (TIME) changes of primary tumors (PT) and corresponding RTs.

Experimental Design: Tumor-infiltrating leukocytes (TIL) of 300 PTs and 108 RTs from two large independent and clinically well-characterized HNSCC cohorts [discovery cohort (DC), validation cohort (VD)] were compared by IHC. mRNA expression analysis of 730 immune-related genes was performed for 18 PTs and RTs after adjuvant chemoradiotherapy (CRT). The effect of chemotherapy and radiation resistance was assessed with an in vitro spheroid/immunocyte coculture model.

Results: TIME analysis revealed overall decrease of TILs with significant loss of CD8+ T cells (DC P = 0.045/VC P < 0.0001) and B lymphocytes (DC P = 0.036/VC P < 0.0001) in RTs compared with PTs in both cohorts. Decrease predominantly occurred in RTs after CRT. Gene expression analysis confirmed loss of TILs (P = 0.0004) and B lymphocytes (P < 0.0001) and showed relative increase of neutrophils (P = 0.018), macrophages (P < 0.0001), dendritic cells (P = 0.0002), and mast cells (P = 0.0057) as well as lower overall expression of immune-related genes (P = 0.018) in RTs after CRT. Genes involved in B-lymphocyte functions and number of tertiary lymphoid structures showed the strongest decrease. SPP1 and MAPK1 were upregulated in vivo and in vitro, indicating their potential suitability as therapeutic targets in CRT resistance.

Conclusions: HNSCC RTs have an immunosuppressive TIME, which is particularly apparent after adjuvant CRT and might substantially contribute to poor therapeutic response and prognosis.