Surface damage of resonator of semiconductor laser controlled by light intensity enhancement

Abstract

To improve the life of semiconductor laser, the size of semiconductor laser resonator surface damage must be studied to determine the catastrophic degradation mechanism of semiconductor laser. In this paper, the light intensity distribution of the GaAs laser resonator surface with a wavelength of 980 nm is studied under the condition of a local heat source. In order to effectively describe the influence of resonator defects on the light intensity of semiconductor lasers, according to different sizes and types of defects, the cuboid defect model and the sphere defect model are set up. The internal light intensity distribution of different sizes of micro-defect resonator surface and non-defect resonator surface is compared and analyzed, and the light intensity increase multiple is used to evaluate the influence of defect size on light intensity. The results show that under the same parameters, the irregularity of the sphere defect leads to a greater intensity enhancement than that of the cuboid defect. The size of the micro-defects is the main mechanism that causes the intensity of the resonator surface to increase, and at the same time affects the damage propagation of the laser resonator surface. It can be quantitatively predicted that the maximum light intensity will be produced when the defect size (length, width and depth) is similar to the wavelength of the semiconductor laser.