Abstract-First Terahertz-range Experiments on Pump – Probe Setup at Novosibirsk free Electron Laser

Yulia Yu.Choporova, Vasily V.Gerasimov, Boris A.Knyazev, Sergey M.Sergeev, Oleg A.Shevchenko, Roman Kh.Zhukavin, Nikolay V.Abrosimov, Konstantin A.Kovalevsky, Vladimir K.Ovchar, Heinz-Wilhelm Hübers, Gennady N.Kulipanov, Valery N.Shastin, Harald Schneider, Nikolay A.Vinokurov

https://www.sciencedirect.com/science/article/pii/S1875389216303224

A single-color pump-probe system has been commissioned at the Novosibirsk free electron laser. The laser emits a tunable monochromatic terahertz radiation. To prove the proper system operation, we investigated the time-resolved absorption of a sample of n-type germanium doped with antimony, which was previously investigated at the FELBE facility, in the temperature range from 5 to 40 K. The measured relaxation time amounted to about 1.7 ns, which agreed with the results obtained at the FELBE. The results of pump-probe measurements of non-equilibrium dynamics of hot electrons in the germanium crystal at cryogenic temperatures are presented for wavelengths of 105, 141 and 150 μm.