Thickness optimization for an anti-ASE cap in a thin disk laser considering dioptric power and aberration-induced loss

摘要

A numerical model is developed to analyze the optical path difference (OPD) of a capped disk with different thickness anti-ASE caps. The spherical and aspherical parts of the OPD are described by dioptric power and diffraction loss, which are used to evaluate the stability range of the resonator and output power of a thin disk laser, respectively. The analytical results show that the anti-ASE cap increases thermal aberration and diffraction loss compared with the uncapped disk. However, with a particular thickness anti-ASE cap, the dioptric power of the capped disk almost keeps constant with the increase of pump power density, which will be beneficial to designing a stable resonator with large fundamental mode size. At the same time, the diffraction loss will reach the maximum value at this thickness, too. Thus, weighing the thermal lens effect and diffraction loss will be important for designing an anti-ASE cap with an optimal thickness to realize higher-power laser generation. (c) 2018 Optical Society of America.