Rotating beams in a solid-state laser with a nonplanar ring cavity

Experimental results for a CW garnet ring laser with a nonplanar cavity show that modes with an angular symmetry of 360 deg/n (n = 3, 4, 5, . . .) undergo rotation both inside and outside the cavity. The beam rotation slows with increasing distance to the center of the active element; the degree of rotation increases with increasing pump power at various values of n. An expression for the calculation of the rotation angle is presented.