Sensitivity of PbSnTe:In films to submillimeter radiation under conditions of field electron injection

Based on the concept of injection currents in the PbSnTe:In alloy, the mechanism of photosignal formation in PbSnTe:In films in the submillimeter spectral range at liquid-helium temperatures was considered. It was shown that the existence of energy-distributed electron trap levels controlling the features in current-voltage characteristics can cause extrinsic photoconductivity. For such sensitivity to submillimeter radiation, its spectral dependence should be related to the injection level controlling the filling of traps with different energies. The sensitivity initiation mechanism caused by the interaction of submillimeter radiation with the PbSnTe:In phonon subsystem was considered. Such a process can result in an increase in the static permittivity and, hence, an increase in the injection current.