Room-temperature, mid-IR (/spl lambda/ = 4.7 /spl mu/m) electroluminescence from single-stage intersubband GaAs-based edge emitters

Strong room-temperature intersubband-emission is obtained at 4.7 microns by using deep quantum wells and high barriers in the active region. The emission linewidth is narrow (/spl sim/20 meV) and the 80 K to 300 K emission ratio is low (/spl sim/2).