Effect of phase imperfections on high-order mode selection with intracavity phase elements

摘要

To obtain a laser beam containing only one pure high-order transverse mode, one can insert a binary phase element (BPE) into a laser resonator. I investigate the effect of deviations in the discontinuous height of the BPE on the selection of high-order Hermite-Gaussian (HG) modes. Both matrix-diagonalization and numerical Fox-Li calculations to obtain the loss per pass and beam propagation factor of the output beam obtained with a deviated BPE are performed. Experimental results obtained with a Nd:YAG laser operated with HG (1,0) and HG (1,1) transverse modes are presented and compared with theoretical modes.