HgCdTe double heterostructure diode lasers grown by molecular-beam epitaxy

Abstract

While HgCdTe has been used extensively to fabricate high performance photodiodes and focal plane arrays, little has been done to apply this technology to light emitting devices. We recently succeeded in fabricating and operating the first HgCdTe diode laser. Here we discuss the early results in detail, and present new results on an expanded range of operation. The stripe-geometry double-heterostructure lasers were grown by molecular-beam epitaxy. Active layer thicknesses ranged between 0.9 and 1.4 μm, and the p+ and n+ confinement layers were in situ doped up to 1018 cm−3 with arsenic and indium, respectively. Three double heterostructures were grown, and they all produced working lasers. The devices were operated under pulsed current at temperatures between 40 and 90 K. At 77 K, the emission wavelengths were 2.9, 3.4, and 3.9 μm, and the lowest threshold current density measured was 521 A/cm2. Further characterization data including temperature dependence of the threshold currents, far field patterns, spectral analysis of longitudinal modes, and imaging of the laser emission in a near field configuration are discussed.