Sub‐100 μA current operation of strained InGaAs quantum well lasers at low temperatures

Very low threshold currents (<100 μA) have been achieved in InGaAs strained single quantum well lasers at cryogenic temperatures. Threshold currents of 38 and 56 μA and external quantum efficiency ∼1 mW/mA have been demonstrated under cw operation condition at temperatures of 6 and 77 K, respectively. The external quantum efficiency increased by about a factor of 2 at low temperatures (<100 K) in comparison to that at room temperature. These results are relevant to the prospect of integration of semiconductor lasers with low temperature electronics for high performance