Improved ultraviolet photorefractive properties of vanadium-doped lithium niobate crystals.

A series of vanadium-doped lithium niobate (LN:V) crystals has been grown and their photorefractive properties were investigated. For 0.1 mol. % V-doped LiNbO(3), a fast photorefractive response of 160 ms was obtained with a 351 nm laser and a total light intensity of 583 mW/cm(2). The measurements of the x-ray photoelectron spectrum and electron paramagnetic resonance show that V(3+), V(4+), and V(5+) ions exist in these LN:V crystals. V(3+) and V(4+) ions correspond to the 420 and 475 nm absorption peaks, respectively. The fast photorefractive response and high sensitivity indicate that LN:V is a suitable candidate for UV photorefractive applications.