窄脊型波导半导体激光器偏振与横模关系研究OA北大核心CSTPCD

A numerical calculation model of the narrow ridge waveguide was established based on the effective refrac-tive index method.The relationship between the polarization characteristics and the transverse mode of the InGaAs quantum well narrow ridge waveguide semiconductor laser was studied experimentally.According to theoretical calcula-tions,the effective refractive index difference of the TM-like mode in the ridge waveguide is larger in the direction of the slow axis.The confinement factors of the TM-like mode are larger than those of the TE-like mode,and the slow-ax-is high-order mode is more likely to appear.As the height of the ridge waveguide increases,the fast-axis high-order modes are truncated,and the confinement factor of the TE00-like mode gradually increases to be similar to that of the TM00-like mode.The slow-axis high-order mode is suppressed due to its large scattering loss,theoretically achieving high polarization,and near diffraction limit beam-quality laser output.In terms of experiments,a narrow ridge wave-guide semiconductor laser with a high polarization extinction ratio and a fundamental transverse mode was fabricated by the gain polarization characteristics of quantum well materials and by designing the height and width of the ridge.