In–HgCdTe–In structures with symmetric nonlinear I–V characteristics for sub-THz direct detection

Abstract

This paper reports on the development and investigations of In–Hg₁₋ₓCdxTe–In structures with symmetric nonlinear I–V curves that are sensitive to sub-terahertz radiation. It is shown that at low currents photoresponse of the detectors based on these structures is due to the presence of potential barriers at the contacts. The dependences of the photoresponse as a function of the bias current are measured at the radiation frequency ν = 140 GHz in the 77–300 K temperature range. The studied structures may be used as detectors of sub-terahertz radiation at room temperature or under weak cooling. The calculated NEP of investigated In–n-Hg₀.₆₁Cd₀.₃₉Te–In detectors was 3.5·10⁻⁹ W/Hz¹/², if taking into account thermal and shot noise.