Polarization-sensitive photoresponse of the CuSe/Se nanocomposite prepared by vacuum thermal deposition

•The CuSe/Se bilayer consisting of nanocrystalline CuSe and amorphous Se films was synthesized.•Polarization dependent photocurrent was observed in the CuSe/Se bilayer irradiated with femtosecond laser pulses.•It was found that the photoresponse of the CuSe/Se bilayer is helicity sensitive.•The polarization-sensitive photoresponse of the CuSe/Se bilayer originates from the surface photogalvanic effect. We report on the generation of the polarization-sensitive photocurrent in the thin film of the CuSe/Se nanocomposite irradiated by femtosecond pulses of Ti:S laser. CuSe/Se bilayer consisting of nanocrystalline CuSe and amorphous Se films was obtained using successive deposition of Cu and Se on a glass substrate in the course of vacuum thermal evaporation. Synthesized bilayers were characterized using optical transmittance and Raman spectroscopy, optical, atomic force and scanning electron microscopy and X-ray diffractometry. It is demonstrated that in the longitudinal configuration, the photocurrent propagating along the plane of incidence is maximum for the p- and vanishes for the s-polarized excitation beam. In the transverse configuration, the photocurrent propagating perpendicular to the plane of incidence is an odd function of the polarization azimuth of the linearly polarized excitation beam and vanishes when it is either p- or s-polarized. We show that for an elliptically polarized excitation beam the polarity of the transverse photocurrent reverses when rotation direction of the electric field vector changes. Both longitudinal and transverse photocurrents are odd functions of the angle of incidence and can be explained in terms of the surface photogalvanic effect.