Abstract

Q-switching of solid-state lasers is a common method for producing a high-energy laser pulse source, however, pulse energy, pulse duration and pulse repetition rate are limited by the cavity dynamics and are not independent. An alternative way to generate a more independently controllable set of pulsed laser parameters is to use a low average power (<1mW) gain-switched diode seed laser (electrically-controlled pulse duration and pulse repetition rate) which is then power-amplified in a system with extremely high gain amplifier system (~10⁵ or more) to boost the average power, pulse energy and peak power to levels required for applications (e.g. industrial material processing). Whilst this configuration is commonly used in fibre laser amplifier system, the peak powers are limited by optical damage and maximum gain limited by amplified spontaneous emission (ASE) [1]. Here we present an investigation of a MOPA-configuration of a diode-seed at 1064nm amplified in single-stage and two-stage Nd:YVO₄ amplifier(s) in a bounce geometry configuration [2], where bulk geometry permits much higher peak power operation and favourably low ASE, compared to fibre amplifiers.

© 2015 IEEE