Investigation of anisotropic thermal lens effect in a dual-polarized Nd:YLF laser

Abstract

The anisotropic thermal lens effect of a dual-polarization Nd:YLF laser is experimentally investigated by measuring the transverse beat frequency between TEM0,0 and TEM1,0 modes in the self-pulsing operation, and focal lengths of thermal lensing for both polarizations can be accurately determined. The focal length of the thermal lens for pi polarization was observed to be negative and varies from -1.1 to -0.5 m for the absorbed pump power increasing from 1.7 to 3.8 W. For sigma polarization, the focal length of the thermal lens was determined to be positive and varies from 1.2 to 0.9 m for the absorbed pump power increasing from 8.4 to 10.9 W. The sensitivity factors of the thermal lens for both polarizations were evaluated to be M-pi = -0.54 m(-1) /W and M-sigma = 0.1 m(-1)/W, respectively. (C) 2020 Optical Society of America