Room-Temperature\nNear-Infrared Lasing from GaAs/AlGaAs\nCore–Shell Nanowires Based on Random Cavity

Abstract

Room-temperature lasing based on low-dimensional GaAs\nnanowires\n(NWs) is one of the most critical and challenging issues in realizing\nnear-infrared lasers for nanophotonics. In this article, the random\nlasing characteristics based on GaAs NW arrays have been discussed\ntheoretically. According to the simulation, GaAs/AlGaAs core–shell\nNWs with an optimal diameter, density, and Al content in the shell\nhave been grown. Systematic morphological and optical characterizations\nwere carried out. It is found that the GaAs NWs with the additional\ngrowth of the AlGaAs shell exhibit improved emission by about 2 orders\nof magnitude at low temperatures, which can be attributed to the suppression\nof crystal defects. At room temperature, lasing was observed with\na threshold around 70.16 mW/cm², and the random lasing\nmechanism was discussed in detail. This work is of great significance\nfor the design of random cavities based on semiconductor NWs, which\nis important for optoelectronic integration.