A study is presented on the optical damage and photovoltaic behaviour of proton-exchanged LiNbO<sub>3</sub> waveguides in the α-, β<sub>1</sub>-phases as well as reverse-exchanged guides. The intensity threshold for optical damage has respectively been found 40, 1.5·10<sup>3</sup> and 2·10<sup>4</sup> W/cm<sup>2</sup>, as measured by the loss of linearity between the in- and out-coupled intensities in a single beam configuration. The photocurrent versus in-coupled intensity curve appears superlinear for α-guides and linear for β<sub>1</sub> and reverse guides. The initial linear stage of the curve shows photocurrent values for reverse and β<sub>1</sub> guides respectively five times and an order of magnitude smaller than for α-guides.
© 2003 Optical Society of AmericaPDF Article