Stretching rainbows to reveal THz fingerprints at high repetition rate

Dispersive Fourier method gives access to spectral information by mapping them in the time domain. This facilitates shot-to-shot spectroscopy of rapidly changing systems. We adapted this technique to demonstrate time-resolved THz spectroscopy at 50 kHz repetition rate by encoding the THz waveform onto the spectral components of spectrally broadened (NIR) ultrafast laser pulses.