Abstract

In contrast to semiconductor lasers emitting at a wavelength less than about 1μm, the observed threshold current density in longer wavelength lasers cannot be satisfactorily accounted for in terms only of the radiative recombination that should accompany population inversion. It is necessary to postulate an additional non-radiative process. Also a reduced incremental efficiency of lasing is observed that suggests the presence of optical absorption. The threshold current density should theoretically decrease with wavelength λ approximately as λ⁻². At low temperatures, this is approximately true, but above room temperature the variation with λ completely reverses, giving a greatly enhanced temperature sensitivity at longer wavelengths.

© 1982 Optical Society of America