Two-Octave-Spanning Dual-Oscillator Field-Resolved Infrared Spectrometer Recording at kHz Rates

Field-resolved infrared spectroscopy (FRIS) is an emerging technique, where not only the spectrum but also the spectral phase of a sample is recorded, with the potential of improved signal-to-noise ratios (SNR) with respect to traditional spectroscopic techniques [1]. State-of-the-art FRIS systems are based on Yb:YAG thin disk lasers, which can provide μJ level pulse energy to drive an intra-pulse difference frequency generation (IPDFG) process to provide the mid-infrared (MIR) radiation. The IPDFG process yields rather low conversion efficiency (0.03%), and a coverage limited to the range 6.0-12.5 μm [2]. In this work, we present a high-acquisition-speed FRIS system based on Cr:ZnS laser technology, increasing the spectral coverage to two octaves.