THz Undulator Beamline @ BL3

The THz undulator beamline has been designed to provide coherent femtosecond (fs) – picosecond (ps) THz pulses for pump-and-probe experiments with the fs VUV pulses from FLASH. First light has been delivered into the FLASH experimental hall 'Albert Einstein' in November 2007. The THz pulses are generated by a purpose built undulator implemented in series to the VUV undulators. The design of the beamline allows to overlap a VUV pulse and a THz pulse generated by the same electron bunch at the end of BL3. The pulses should therefore be naturally synchronized. The expected pulse energies lie within the microjoule regime.

  THz radiation with the following parameters is available for pump-and-probe experiments at BL3:

  • tunable: 10 ‐ 300 μm; up to 100 μJ/pulse; ~10% bandwidth,
  • broadband at 200 μm; up to 10μJ/pulse; ~100% bandwidth
  • synchronized and phase stable to X-­ray pulses (down to 5 fs)
  • delivered to the experiment via vacuum beamline as:
  • (i) ultra-­‐high vacuum (~10­‐8 mbar), shorter delay between THz and X-­‐ray (~4 m path difference), can accommodate up to 0.3 m wide setup;
  • (ii) high vacuum (pressure ~10­‐6 mbar), longer delay between THz and X-­‐ray (~7 m path difference); can accommodate up to 2 m wide setup
CONTACT THz Beamline:
Rui Pan
E-Mail: Rui Pan
Phone: +49 (0)40 8998 4526, mobile: 94526
Location: 49 / 115
Seung-gi Gang
E-Mail: Seung-gi Gang
Phone: +49 (0)40 8998 4340
Location: 49 / 109
Marc Temme
E-Mail: Marc Temme
Phone: +49 (0)40 8998 2301
Location: 49 / 106


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