Extremely low threshold current AlGaAs buried-heterostructure quantum well lasers grown by liquid phase epitaxy

Abstract
Data are presented on AlGaAs single quantum well buried-heterostructure lasers grown by two-step liquid phase epitaxy (LPE). The base laser structures were grown by low-temperature LPE in the temperature interval of 600–400 °C. Broad-area threshold current densities of 300 A/cm2 were measured for 1-mm-long lasers. The buried heterostructure was formed in the second LPE process including in situ selective mesa melt etching. Threshold currents of 1.3 mA in a continuous regime were obtained for uncoated lasers having 125-μm-long cavities.