High-temperature (T /spl ges/ 470 K) pulsed operation of 5.5 /spl mu/m quantum cascade lasers with high-reflection coating

High-temperature operation of 5.5 /spl mu/m strain-compensated InGaAs/InAlAs quantum cascade lasers with high-reflection (HR) coating is presented. A threshold current density of 7.5 kA/cm/sup 2/ was observed at the record high temperature of 470 K using HR coating on both facets with reflectivities of 99.6 and 80.2%, respectively.