Nonstationary photocurrent and pyroelectric response in aged Sn2P2S6 films

The photoelectric and pyroelectric properties of Sn2P2S6 films were studied by a dynamic method under excitation by periodic rectangular laser beam pulses (λ = 6328 Å). In this case, an appearance of the nonstationary photoelectric response in the films under visible light irradiation (extrinsic excitation) was observed. It was found that temperature dependence of the unsteady current is connected to features of spontaneous polarization behaviour in Sn2P2S6 thin films. A nature of the nonstationary photoelectric response existence due to an electric field of the potential barrier near an interface is discussed.