Photoinduced phase transition and relaxation in bare SrTiO_3 single crystals

摘要

The photoinduced insulator-metal phase transition and relaxation characteristics have been investigated in bare SrTiO_3 single crystals. The photoinduced relaxation time constant after the irradiation shows an increase with increasing temperatures. The SrTiO_3 single crystal has a cutoff wavelength and an absorption edge of spectrum at about 385 nm, which agrees well with the band gap. The photocurrent responsivity is 1.36 × 10~(-5)A/W at 300 nm wavelength. The relative change in resistance is more than above six orders at room temperature, possessing potential applications in ultraviolet sensitive and detecting devices.