Fast photogalvanic response of a Bi12SiO20 crystal

A photoelectric response of a Bi12SiO20 crystal grown in an argon atmosphere on a linearly polarized light (which is referred to as the linear photogalvanic effect) is reported for the first time in the nanosecond-time domain. Optimal geometry for detection of the photo-induced current concerning the orientation of the polarization state of the incident light in respect to the crystallographic axes of a sample was determined considering both the natural optical activity and light absorption of sillenite crystals. Spectral dependence of the photogalvanic current was measured in the visible part (410 - 610 nm) of the spectrum. Temporal shape of light-induced electric-current pulses observed at different experimental conditions is discussed. Obtained results are believed to show that sillenite crystals are very prospective for development of different ultra-fast optoelectronics devices.