High-repetition-rate femtosecond optical parametric chirped-pulse amplifier in the mid-infrared

Abstract

We discuss a dual-stage optical parametric chirped-pulse amplifier generating sub-100-fs pulses in the mid-infrared at a repetition rate of 100 kHz. The system is based on a 1064 nm pump laser and a 3-4 µm difference frequency generation seed source derived from the output of a femtosecond fiber laser amplifier. Both lasers are commercially available, are diode-pumped, compact, and allow for turn-key operation. Here, we focus our discussion on the design and dimensioning of the optical parametric chirpedpulse amplifier. In particular, we review the available gain materials for mid-infrared generation and analyze the impact of different stretching scenarios. Timing jitter plays an important role in short-pulse parametric amplifier systems and is therefore studied in detail. The geometry of the amplifier stages is optimized through a full 3-dimensional simulation with the aim of maximizing gain bandwidth and output power. The optimized system yields output pulse energies exceeding 1 µJ and an overall gain larger than 50 dB. The high repetition rate of the pump laser results in an unprecedented average power from a femtosecond parametric system at mid-infrared wavelengths. First experimental results confirm the design and the predictions of our theoretical model.

Few‐optical‐cycle light pulses with passive carrier‐envelope phase stabilization

“…The resulting 6 ps pulse width is well matched to the pump pulse width [116,117]. The OPCPA consists of two stages, both using MgO:PPLN crystals, and produces 100 mW average power, corresponding to 1 μJ per pulse.…”

Origin of Unexpected Low Energy Structure in Photoelectron Spectra Induced by Midinfrared Strong Laser Fields

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Dispersion compensation in three-photon fluorescence microscopy at 1,700 nm

“…Although fine-tuning the GDD is possible using Si prisms [6,17,18], adding a Si wafer to the optical beam path is significantly simpler. Since Si wafers of various thicknesses are readily available commercially, the addition of the Si wafer provides a simple, practical solution for dispersion compensation at 1,700 nm.…”