High-temperature luminescence in light-emitting heterostructures with a high potential barriers based on GaSb

摘要

The electroluminescent properties of an n-GaSb-InGaAsSb/p-AlGaAsSb heterostructure with a high potential barrier in the conduction band (large conduction-band offset) at the n-GaSb-InGaAsSb type-Ⅱ heterointerface (ΔEc = 0.79 eV) are studied. Two bands with peaks at 0.28 and 0.64 eV at 300 K, associated with radiative recombination in n-InGaAsSb and n-GaSb, respectively, are observed in the electroluminescence spectrum. In the entire temperature range under study, T = 290 - 480 K, additional electron-hole pairs are formed in the n-InGaAsSb active region by impact ionization with hot electrons heated on the large the conduction-band offset. These pairs contribute to radiative recombination, which leads to a nonlinear increase in the electroluminescence intensity and output optical power with increasing pump current. A superlinear increase in the emission power of the long-wavelength band is observed upon heating in the temperature range T = 290 - 345 K, and a linear increase is observed at T ＞ 345 K. Theoretical calculations have shown that this behavior of the temperature dependence of the optical power caused by competition between the radiative recombination, thermionic emission and Auger recombination.