Ultraviolet laser-induced photovoltaic effects in miscut ferroelectric LiNbO₃ single crystals

This paper investigates the photovoltaic properties of miscut LiNbO₃ single crystal with different thicknesses under irradiation of a 248 nm ultraviolet laser pulse with 20 ns duration without an applied bias. Nanosecond photovoltaic response is observed and faster rise time is obtained in thinner samples. In accord with the 248 nm laser duration, the full width at half maximum of the photovoltaic signals keeps a constant of ～20 ns. With decrease of the crystal thickness, the photovoltaic sensitivity was improved rapidly at first and then decreased, and the maximum photovoltage occurred at 0.38 mm-thick single crystal. The present results demonstrate that decreasing the LiNbO₃ single crystal thickness can obtain faster response time and improve the photovoltaic sensitivity.