Magnonics: Spin waves bridging Spintronics and Photonics

Emmy Noether research group of Dr. Helmut Schultheiß

Mitarbeiter:

Postdocs:

Dr. Lorenzo Fallarino

Dr. Nana Nishida

PhD Students:

Toni Hache

Kai Wagner

Master and Bachelor Students:

Tobias Hula

Lukas Körber

Peter Matthies

Christian Riedel

Tillmann Weinhold

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Within this project we investigate the fundamental connections between spin waves, spin polarized electrons and photons, combining the three recently emerged research directions of magnonics, spintronics and photonics. This research is driven by the demand for new concepts, technologies and materials for information processing since, on one side, electronics is reaching its physical limit of speed due to waste heat generation and, on the other side, photonics lacks fast, electronic control on small length scales. Spin waves, being the fundamental dynamic excitations of ferromagnets with frequencies in the gigahertz to terahertz regime, offer the unique opportunity to merge the best aspects of spintronics and photonics opening new pathways for information processing.

Methods:

• time- and phase-resolved Brillouin light scattering microscopy(TR-µBLS)
• time-resolved magneto-optical Kerr microscopy (TR-µMOKE)
  • all-optical pump-probe: femtosecond laser system
  • microwave excitation: picosecond laser system
• electrical detection via the (inverse) spin Hall effect
• broadband ferromagnetic resonance (FMR) in combination with spin pumping experiments

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Master and Bachelor Thesis Topics:

Interaction of spin waves and spin polarized currents

Using the spin degree of electrons and coherent transport of spin information is one of the grand challenges of condensed matter physics. Spin wave, which are also called magnons, are the fundamental exciation quanta of a ferromagnet and can interact with spin polarized currents. This interaction can be studied on a nanometer lengthscale using magneto-optical techniques such as Kerr-effect and Brillouin light scattering microscopy as well as electrical measurements based on the (inverse) spin Hall effect.

Magneto-Plasmonik

Plasmons are electromagnetic waves propagating along metal-dielectric interfaces. Plasmons as well as magnons are not only interesting from a physicists point of view but are also promising candidates for future information processing technologies superseeding conventional CMOS devices. During a master or bachelor thesis the candidate will invesigate the interaction between magnons and plasmons in metallic/ferromagnetic hybrid devices.

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Publications

Submitted:

• K. Schultheiss, R. Verba, F. Wehrmann, K. Wagner, L. Körber, T. Hula, T. Hache, A. Kakay, A.A. Awad, V. Tiberkevich, A.N. Slavin, J. Fassbender, H. Schultheiss
  "Excitation of whispering gallery magnons in a magnetic vortex"
  (preprint available at arXiv:1806.03910)

Publications 2018

• J. Osten, K. Lenz, H. Schultheiss, J. Lindner, J. McCord, J. Fassbender
  "Interplay between magnetic domain patterning and anisotropic magnetoresistance probed by magneto-optics"
  Phys. Rev. B 97, 014415 (2018), DOI: 10.1103/PhysRevB.97.014415

Publications 2017

• L. Körber, K. Wagner, A. Kákay, H. Schultheiss
  "Spin-wave reciprocity in the presence of Néel walls"
  IEEE Magnetic Letters PP, 99 (2017), DOI: 10.1109/LMAG.2017.2762642
• H. Schultheiss
  "Spins in Formation"
  Physik Journal Nr. 8/9 (2017)
• A.V. Chumak, and H. Schultheiss
  "Magnonics: Spin Waves Connecting Charges, Spins and Photons" (Editorial)
  J. Phys. D: Appl. Phys. 50, 300201 (2017)
• J.A. Otálora, M. Yan, H. Schultheiss, R. Hertel, A. Kákay
  "Asymmetric spin-wave dispersion in ferromagnetic nanotubes induced by surface curvature"
  Phys Rev B. 95, 184415 (2017), DOI: 10.1103/PhysRevB.95.184415 

Publications 2016

• J.A. Otálora, M. Yan, H. Schultheiss, R. Hertel, A. Kákay
  "Curvature-Induced Asymmetric Spin-Wave Dispersion"
  Phys. Rev. Lett. 117, 227203 (2016), DOI: 10.1103/PhysRevLett.117.227203
• H. Schultheiss
  "Optik einmal anders"
  Physik Journal Nr. 10 (2016)
• K. Wagner, A. Kákay, K. Schultheiss, A. Henschke, T. Sebastian, and H. Schultheiss
  "Magnetic domain walls as reconfigurable spin-wave nanochannels"
  Nature Nanotechnology 11, 432 (2016), DOI: 10.1038/NNANO.2015.339
• M. Langer, K. Wagner, T. Sebastian, R. Hübner, J. Grenzer, Y. Wang, T. Kubota, T. Schneider, S. Stienen, J. Linder, K. Lenz, H. Schultheiss, J. Linder, K. Takanashi, R. Arias, J. Fassender
  "Parameter-free determination of the exchange constant in thin films using magnonic patterning"
  Appl. Phys. Lett. 108, 102402 (2016), DOI: 10.1063/1.4943228
• J.A. Otálora, M. Yan, H. Schultheiss, R. Hertel, A. Kákay
  "Curvature-Induced Asymmetric Spin-Wave Dispersion"
  Phys. Rev. Lett. 117, 227203 (2016), DOI: 10.1103/PhysRevLett.117.227203
• H. Schultheiss
  Magnetic domain walls as reconfigurable spin-wave nano-channels (Conference Presentation)
  Proc. SPIE 9931, Spintronics IX, 99313T (2016)

Publications 2015

• T. Sebastian, K. Schultheiss, B. Obry, B. Hillebrands, and H. Schultheiss
  "Micro-focused Brillouin light scattering: imaging spin waves at the nanoscale"
  Front. Phys. 3, (2015), DOI: 10.3389/fphy.2015.00035
• E. Montoya, T. Sebastian, H. Schultheiss, B. Heinrich, R. Camley, Z. Celinski
  "Magnetization Dynamics", Book chapter in Magnetism of Surfaces, Interfaces and Nanoscale Materials, Elsevier (2016)
  ISBN: 978-0-444-62634-9

Publications 2014

• K. Vogt, F.Y. Fradin, J.E. Pearson, T. Sebastian, S.D. Bader, B. Hillebrands, A. Hoffmann, and H. Schultheiss
  “Realization of a spin-wave multiplexer”
  Nature Comms. 5, 3727 (2014)
  DOI: 10.1038/ncomms4727
• A. Hassdenteufel, C. Schubert, B. Hebler, H. Schultheiss, J. Fassbender, M. Albrecht, and R. Bratschitsch
  "All-optical helicity dependent magnetic switching in Tb-Fe thin films with a MHz laser oscillator"
  Optics Express 22, 10017 (2014), DOI: 10.1364/OE.22.010017
• A. Hoffmann, and H. Schultheiss
  "Mesoscale Magnetism"
  Curr. Opin. Solid State Mater. Sci. (2014), DOI: 10.1016/j.cossms.2014.11.004
• N. Tahir, R. Gieniusz, A. Maziewski, R. Bali, M.P. Kostylev, S. Wintz, H. Schultheiss, S. Facsko, K. Potzger, J. Lindner, and J. Fassbender
  "Magnetization Reversal of Disorder-Induced Ferromagnetic Regions in Fe60Al40 Thin Films"
  IEEE Transactions on Magnetics 50, 6101304 (2014), DOI: 10.1109/TMAG.2014.2321564

Selected publications before 2014

• H. Schultheiss, J.E. Pearson, S.D. Bader, and A. Hoffmann,
  “Thermoelectric detection of spin waves”
  Phys. Rev. Lett. 109, 237204 (2012). DOI: 10.1103/PhysRevLett.109.237204
• H. Schultheiss, K. Vogt, and B. Hillebrands,
  “Direct observation of nonlinear four-magnon scattering in spin-wave microconduits”
  Phys. Rev. B 86, 054414 (2012). DOI: 10.1103/PhysRevB.86.054414
• K. Vogt, H. Schultheiss, S. Jain, J.E. Pearson, A. Hoffmann, S.D. Bader, and B. Hillebrands,
  “Spin waves turning a corner”
  Appl. Phys. Lett. 101, 042410 (2012), DOI: 10.1063/1.4738887
• H. Schultheiss, X. Janssens, M. van Kampen, F. Ciubotaru, S. Hermsdoerfer, B. Obry, A. Laraoui, A.A. Serga, L. Lagae, A.N. Slavin, B. Leven, and B. Hillebrands,
  “Direct current control of three magnon scattering processes in spin-valve nanocontacts”
  Phys. Rev. Lett. 103, 157202 (2009), DOI: 10.1103/PhysRevLett.103.157202
• H. Schultheiss, S. Schäfer, P. Candeloro, B. Leven, B. Hillebrands, and A.N. Slavin,
  “Observation of coherence and partial decoherence of quantized spin waves in nano- scaled magnetic ring structures”
  Phys. Rev. Lett. 100, 047204 (2008), DOI: 10.1103/PhysRevLett.100.047204