Ultraviolet photovoltaic effect in tilted orientation LaAlO3 single crystals

Pulsed laser-induced photovoltaic effects were observed in the tilted orientation LaAlO3 (LAO) single crystal wafers without any bias at ambient temperature when the LAO wafers were irradiated by the laser pulses of 246 nm ultraviolet (UV) wavelength. The rise time is 13 ns, and the full-width at half-maximum (FWHM) is 25 ns for the open-circuit photovoltage. The sensitivities of the photovoltage and the photocurrent are 270 mV/mJ and 0.91 mA/mJ for the tilting 20 degrees LAO wafer, respectively. The mechanism of the photo-induced photovoltage in LAO wafers is proposed as the combination of a photoelectric process and a Seebeck one. (c) 2006 Elsevier B.V. All rights reserved.