Group-velocity dispersion emulator using a time lens

We report a novel method to continuously track the temporal evolution of an arbitrary complex waveform as it propagates through a group-velocity dispersion medium by using a single-frequency-driven phase modulator. The proposed method exploits the fact that the frequency spectrum of a given (input) waveform, following a suitable sinusoidal temporal phase modulation, exhibits the same shape as that of a dispersed version of the same temporal waveformafter propagation through a prescribed amount of dispersion. In experiments, we track the dispersion-induced temporal evolution of different optical picosecond pulsed waveforms by tuning the frequency and/or amplitude of the phase modulation signal and observing the resulting shapes in the optical frequency domain. A good agreement is obtained between the measured spectra and predicted temporal shapes of the propagating waveform for different amounts of dispersion. Moreover, the method is successfully applied on a chirped optical pulse to find the optimal pulse compression conditions. (C) 2021 Optica Publishing Group.

Automated summary

The study introduces a novel method to track the temporal evolution of complex waveforms using a single-frequency-driven phase modulator. Experimental results show that tuning the frequency and amplitude of the phase modulation signal allows observation of the temporal evolution of different optical picosecond pulsed waveforms in the optical frequency domain, leading to finding the optimal pulse compression conditions.