Adaptive, high-power, dynamically stable ring resonator

Abstract

Dynamically stable resonators have a stationary TEM00 beam waist inside the laser rod (w30), which is minimal throughout the stability interval and insensitive to changes in pump power. For a given set of resonator parameters (mirror radii and distances between mirrors and rods), the stability interval parameters, which are the limits of the stability interval in terms of the rod’s thermally induced focusing length are determined. In linear resonators, these stability interval parameters cannot be changed independently only by varying resonator distances, and mirrors of different curvature have to be employed. However, our group showed recently that for a symmetric ring resonator containing a pair of curved mirrors, the width of stability interval and the stability interval limit at maximum rod’s focal length can be adjusted continuously and independently only by varying resonator distances once the mirror radius of curvature has been fixed. In this work we demonstrate a project of an adaptive ring resonator that allows the TEM00 - mode resonator to be continuously tuned throughout the whole range of pump powers utilizing standard electromechanics to move the mirrors. Additionally for a given value of pump power, w30 can be varied, thus allowing different beam qualities to be obtained from the same resonator.