2D-Raman-THz Spectroscopy with Single-Shot THz Detection

We present a 2D-Raman-THz setup with multichannel (single-shot) THz detection, utilizing two crossed echelons, in order to reduce the acquisition time of typical 2D-Raman-THz experiments from days to a few hours. This speed-up is obtained in combination with a high repetition rate (100 kHz) Yb-based femtosecond laser system and a correspondingly fast array detector. The wavelength of the Yb-laser (1030 nm) is advantageous, since it assures almost perfect phase matching in GaP for THz generation and detection, and since dispersion in the transmissive echelons is minimal. 2D-Raman-THz test measurements on liquid bromoform (CHBr3) are reported. An enhancement of ∼5.8 times in signal-to-noise ratio is obtained for single-shot detection when comparing to conventional step scanning measurements in the THz time-domain, corresponding to speed up of acquisition time of 34.