Pulse width reduction due to RF filtering in synchronized time-lens source.

Abstract

Synchronized time-lens source has emerged as a promising solution for two-color synchronized ultrashort laser source. Various experiments have demonstrated that the synchronized time-lens source is especially suitable for applications in coherent Raman scattering (CRS) imaging and spectroscopy. In a synchronized time-lens source, phase modulators are typically driven by a filtered high-order harmonic (sine wave) of the fundamental repetition rate of the mode-locked laser. The bandwidth of the narrowband RF filter for this high-order harmonic is thus a programmable parameter for optimizing the performance of the time-lens source. In this paper, through both analytical and numerical investigations we demonstrate that, manipulating the bandwidth of RF filtering can reduce the pulse with of the synchronized time-lens source. This is potentially helpful for reducing the overall system complexity or extending the synchronized time-lens source to the femtosecond level.