Abstract

Phase conjugating mirrors (PCM) based on stimulated Brillouin scattering (SBS) in gaseous, liquid or solid materials are used to improve the beam quality of solid state lasers [1]. As a consequence of the nonlinear reflectivity, for a reflection of e.g. 2% a minimum laser light power or energy, referred as the SBS-threshold, is needed. Standard SBS mirror geometry in which the laser beam is focused into the SBS material exhibits peak power thresholds in the range of several 10 kW up to several 100 kW depending on the SBS material. Due to this high thresholds these mirrors can only be used with pulsed laser systems. To compensate phase distortions of cw-pumped or quasi-cw lasers new SBS-PCMs have to be developed [2, 3]. In addition to a low threshold in the range of 1 W, these PCMs shall have a large dynamic range, a high reflectivity and low coherence demands, too.

© 2000 IEEE