Two-frequency stimulated emission in Hg(Cd)Te/CdHgTe heterostructure

In this work, we studied the spectra of stimulated emission of a waveguide heterostructure with quantum wells based on HgCdTe. In the course of the studies, we used optical pumping, at wavelengths of 2 and 2.3 $\mu$m, which are mainly absorbed, in the barriers and quantum wells, respectively. It was found that in both cases optical pumping leads to stimulated emission, with a wavelength corresponding to the energy of the fundamental transition in quantum wells, it being 138 meV. With pumping absorbed in barriers, it was found that a short-wavelength emission line with an energy of 248 meV appeared on the spectra, which can be attributed to transitions involving deep donor levels. At liquid nitrogen temperature, increasing the pumping intensity leads to the appearance of a narrow peak in the short-wave line and, by selecting the pumping parameters, two-frequency generation at 5 and 7 $\mu$m wavelengths can be achieved.