50 mW CW-operated single-mode surface-emitting AlGaAs lasers with 45 degrees total reflection mirrors

Abstract
The authors report on the fabrication and testing of surface-emitting AlGaAs 3.5 mu m ridge lasers with etched mirrors and 45 degrees internal deflectors. The 45 degrees mirror coupling coefficient and the resulting threshold current penalty have been analyzed theoretically and experimentally. A surface-emitted optical power of 50 mW CW at 26 mA threshold current and external differential efficiency of 57% has been achieved in lateral fundamental-mode operation. The optical power density of 14 mW CW per micrometer ridge width is the highest reported to date and produces two-dimensional surface-emitting laser arrays of diffraction-limited beam quality suitable for optical storage applications.