High temperature operating (>80°C) 795-nm VCSEL based on InAlGaAs MQWs active region

Design of the active region and analysis of temperature sensitivity of high-temperature operating 795-nm special VCSELs for Chip-Scale Atomic Clock (CSAC) are presented. Composition and thickness of the InAlGaAs multiple quantum wells (MQWs) are optimized at room and elevated temperatures. Temperature sensitivity of the threshold current is analyzed by calculating the temperature dependence of cavity-mode gain over a broad temperature range (25°C-150°C). A self-consistent VCSEL model based on quasi 3D finite element analysis is employed to investigate selfheating effects and temperature distribution in the proposed structure. Output power of 2.5mW is expected from 10μm aperture VCSELs at 10mA current at ambient temperature of 358K.