Analysis of Thermal Aberrations in the Power Amplifiers of a 10-Hz 100-TW Ti:sapphire Laser

Abstract

We analyze thermally-induced aberrations in the two power amplifiers of a 10-Hz, 100-TW Ti:sapphire laser. The thermal lensing effect, resulting in a focus shift, is investigated by calculating the thermal focal length with the generalized ray-transfer matrix. To characterize the effect of higher-order thermal aberrations, such as coma, trefoil, spherical aberration, and so on, we calculate the beam quality factor, M(2); with the wavefront of the laser beam. We show that the induced higher-order thermal aberrations degrade the laser beam quality.