Contact

Porträt Dr. Deinert, Jan-Christoph; FWKI

Dr. Jan-Christoph Deinert

Coordinator TELBE user facility
High-field THz driven Phenomena
j.deinertAthzdr.de
Phone: +49 351 260 3626

Dr. Igor Ilyakov

i.ilyakovAthzdr.de
Phone: +49 351 260 3616

TELBE: High-Field High-Repetition-Rate Terahertz facility @ ELBE

The TELBE facility consists of unique highly intense accelerator-based sources of terahertz radiation in conjunction with a wide range of endstations for probing ultrafast terahertz-induced dynamics in various states of matter with highest precision. The TELBE undulator source offers CEP-stable, tunable, narrowband THz radiation with pulse energies of several microjoules at high repetition rates (see figure below). A synchronized coherent diffraction radiator provides broadband single-cycle pulses, which are typically used as a timing reference.

TELBE Pulsenergien und typische Feldtransienten (2020) ©Copyright: Dr. Deinert, Jan-Christoph

Typical TELBE undulator terahertz pulse energies as a function of terahertz frequency (left, 50 kHz repetition rate), and representative electric field transients for the undulator source (top right, after 0.3 THz bandpass filter) and the coherent diffraction radiator (CDR) (lower right).

 

As part of an upgrade of the ELBE accelerator one electron beamline has been modified to allow for the generation and acceleration of ultra short (< 200 fs) highly charged (> 250 pC) electron bunches. This upgrade enables the operation of High-Field THz sources based on superradiant THz emission at the ELBE accelerator and thereby opens up the opportunity to generate carrier-envelope phase stable high-field THz pulses with extremely flexible paramaters with respect to repetition rate, pulse form and polarization. Since 2014 the electron beamline and the TELBE facility have been operational [1,2].

TELBE is a user facility, open to the worldwide scientific community. Proposals can be submitted via the central user portal. The available in-lab laser infrastructure allows THz-pump laser-probe experiments within a wide range of experimental schemes and probe beam properties.

Please note that the TELBE sources are under constant development, current achievable parameters are (as of July 2026):

Radiator type Undulator CDR
Electron charge / pC up to 250
Repetition rate / kHz 10 to 500
Pulse energy / μJ ≤ 10 ≤ 0.25
Bandwidth / % 20 100
Frequency range / THz 0.1 - 2.5 0.1 - 1.1

For further details and discussions of potential projects and experimental ideas please contact the TELBE team. The strong in-house expertise on ultrafast spectroscopic methods and the broad scientific background of the TELBE team allows strong on-site support during experimental planning, set-up and execution.

Pulses from both radiator types are transported into a dedicated laser laboratory which is equipped with the following infrastructure:

  • fs laser-amplifier system 1: Coherent, Inc. RegA 9040
  • fs laser-amplifier system 2: Coherent, Inc. Legend Elite
  • 7 T split-coil magnet with optical access: OXFORD INSTRUMENTS SPECIAL SM4000-10
  • Optical cryostats (liquid He cooling, vacuum and contact gas environment, 3.4 K to 500 K)
  • High-Field THz pump probe set-ups based on optical rectification, photoconductive emitters,...
  • FPGA-based online pulse-to-pulse THz diagnostic endstation (fs arrivaltime, THz - spectrum & pulse energy,...) [4]
  • TR - Faraday rotation endstation
  • TR - THz (harmonic) emission endstation [5]
  • Extensive THz manipulation and diagnostics equipment

We further operate additional laser laboratories equipped with the following laser infrastructure for optical and THz experiments:

  • fs laser-amplifier system 1: Coherent, Inc. Astrella HE
  • fs laser-amplifier system 2: Coherent, Inc. RegA 9000
  • TR - Scattering-type nearfield microscopy [6]

Contact:

Dr. Jan-Christoph Deinert (TELBE coordinator)

Dr. Igor Ilyakov (TELBE beamline scientist - THz characterization and optical setups)

Dr. Alexey Ponomaryov (TELBE beamline scientists - sample environments and high magnetic fields)

Dr. Thales VAG de Oliveira (TELBE/FELBE beamline scientists - THz nanoscopy)

Prof. Dr. Sebastian Maehrlein (Department head)

[1] B. Green et. al., "High-field High-repetition-rate Sources for the Coherent THz Control of Matter", Scientific Reports 6 22256 (2016). (nature.com)

[2] S. Kovalev et al., "Probing ultra-fast processes with high dynamic range at 4th-generation light sources: Arrival time and intensity binning at unprecedented repetition rates", Struct. Dyn. 4 024301 (2017). (scitation.org)

[3] S Kovalev et al., "Selective THz control of magnetic order: new opportunities from superradiant undulator sources", J. Phys. D: Appl. Phys. 51, 114007 (2018). (HZDR repository)

[4] A. Ponomaryov et al., "FPGA-based measurements of the relative arrival time of a high-repetition rate, quasi-cw fourth generation light source", Rev. Sci. Instrum. 95, 103008 (2024). (AIP publishing)

[5] Hafez, H.A., Kovalev, S., Deinert, JC. et al., "Extremely efficient terahertz high-harmonic generation in graphene by hot Dirac fermions" Nature 561, 507–511 (2018). (nature.com)

[6] F. Kuschewski et. al., "Optical nanoscopy of transient states of matter", Scientific Reports 5, 12582 (2015). (nature.com)