Electron-beam-pumped Al_xGa_1–xSb semiconductor laser

Abstract

Stimulated emission from AlxGa1–xSb solid solutions, excited by an electron beam and cooled with liquid nitrogen, was observed for the first time. This emission was observed throughout the direct-gap range of compositions and the emission wavelength was within the range 1.1–1.6 μ. The dependence of the forbidden-band width Eg on the solid-solution composition x was determined and the point of transition from the direct- to the indirect-gap structure was found (xc≈0.25, Egc≈1.145 eV). A discrepancy between the experimental results and a graphical determination of the dependence Eg(x) was due to the influence of donor levels (Ed≈20 meV) below the indirect L minimum. The parameters of a sealed electron-beam-pumped laser made of such a material were determined.