Optical parametric multi-pass cell amplifier

TL;DR

The paper introduces the Optical Parametric Multi-Pass Cell Amplifier (OPMPC), a hybrid system that combines the advantages of multi-pass cell and optical parametric amplifier technologies to achieve high efficiency, broadband tunability, and high-quality ultrafast pulses.

Contribution

It presents a novel hybrid architecture that overcomes the limitations of existing parametric and multi-pass amplification schemes, demonstrating record efficiency and stable ultrafast pulse generation.

Findings

Achieved 43% pump-to-signal conversion efficiency.

Produced 1500 nm pulses compressed to 48 fs.

Demonstrated stable, high-quality ultrafast pulse output.

Abstract

Ultrafast lasers with simultaneously high average and peak power have become indispensable for driving a multitude of applications, including high-harmonic generation, strong-field physics, and particle source applications. Both parametric amplifiers and post-compressed Ytterbium lasers have emerged as prime platforms to meet these demands. While multi-pass cell (MPC) based post-compression offers broadband output with high beam quality, it provides limited wavelength tunability and suffers from temporal contrast degradation. Conversely, optical parametric amplifiers (OPAs) provide spectral tunability and high temporal contrast but they are limited by low pump-to-signal conversion efficiency and spatial beam inhomogeneities. Here, we introduce the Optical Parametric Multi-Pass Cell Amplifier (OPMPC), a hybrid architecture that overcomes the limitations of both schemes. Our approach utilizes two non-collinearly intersecting MPCs providing broadband parametric amplification of the seed pulses and complete idler removal after each pass through the crystal, thereby suppressing back-conversion. We experimentally demonstrate a record pump-to-signal power conversion efficiency of 43% using a 1030 nm pump at a 1 kHz repetition rate with a pulse energy of 174 $\mu$J. The amplified signal at 1500 nm exhibits excellent beam quality, power and spectral stability and is compressed to 48 fs, demonstrating a new platform for ultrafast pulse generation.