SELF-CONSISTENT SPATIAL MODE ANALYSIS OF SELF-ADAPTIVE LASER-OSCILLATORS

A theoretical analysis involving ABCD ray transfer matrices is used to find the self-consistent fundamental spatial mode solutions of self-a daptive laser resonators. The resonators investigated consist of a non linear medium in a self-intersecting loop geometry together with a fee dback output coupler mirror and additional intracavity elements. A sim plified system without intracavity elements is analyzed initially, and an analytic expression for the mode solution is deduced. Addition of an intracavity lens is shown to permit enhancement of the quality of t he phase-conjugation process as well as control of the mode size. The theoretical analysis is extended to model an experimental self-adaptiv e laser oscillator utilizing gain-grating formation in a solid state N d:YAG laser amplifier. Good agreement is found between the theory and the experimental results. (C) 1998 Optical Society of America.