Low-threshold InAs-based interband cascade lasers operating at high temperatures

InAs-based interband cascade (IC) lasers with improved optical confinement have achieved high-temperature operation with a threshold current density as low as 247 A/cm2 at 300 K for emission near 4.6 μm. The threshold current density is the lowest ever reported among semiconductor mid-infrared lasers at similar wavelengths. These InAs-based IC devices lased in pulsed mode at temperatures up to 377 K near 5.1 μm. Narrow-ridge devices were able to operate in continuous-wave mode at temperatures up to 308 K near 4.8 μm. The implications and prospects of these results are discussed.