Effect of the optical characteristics of semiconductor resonator structures on the amplitudes of their thermal radiation lines

We investigated, both theoretically and experimentally, the dependence of the intensity of spectral lines of thermal radiation from plane-parallel semiconductor resonator structures on their optical parameters (volume absorption and coefficients of reflection from surfaces). The investigations were performed in the spectral region of absorption by free charge carriers (λ = 3–17 μm). It is shown for such structures that the amplitudes of thermal radiation lines depend non-monotonically on the transmission factor. We determined the optical parameter values for a resonator structure that are optimal when forming comb radiation spectrum. The conditions are found under which the intensity of lines of thermal radiation from a semiconductor plane-parallel layer approaches that of thermal radiation from a blackbody.