1 kW, 10 mJ, 120 fs coherently combined fiber CPA laser system

TL;DR

This paper presents a high-power ultrafast fiber laser system that coherently combines 16 amplifiers to produce 10 mJ pulses at 1 kW power with 120 fs duration, maintaining high beam quality.

Contribution

It demonstrates a novel coherent combination of multiple fiber amplifiers achieving high energy and power with ultrashort pulses in a compact system.

Findings

Achieved 10 mJ pulse energy at 1 kW average power.

Maintained near diffraction-limited beam quality.

Implemented a helium-protected compressor to reduce nonlinear effects.

Abstract

An ultrafast fiber chirped-pulse amplification laser system based on coherent combination of 16 ytterbium-doped rod-type amplifiers is presented. It generates 10 mJ pulse energy at 1 kW average power and 120 fs pulse duration. A partially helium-protected, two-staged chirped-pulse amplification grating compressor is implemented to maintain the close to diffraction-limited beam quality by avoiding nonlinear absorption in air.