Abstract

We report what we believe to be the first demonstration of a guided-wave process in the nonlinear material rubidium titanyl arsenate (RTA, RbTiOAsO₄). RTA is an attractive alternative to potassium titanyl phosphate (KTP) for electric field poling and waveguide fabrication. Its low ionic conductivity is compatible with the electric field poling process, its d-33 nonlinear coefficient is comparable to that of KTP,¹ and its infrared transparency range extends to longer wavelengths than in KTP.² Previous poling results in KTP have been obtained using hydrothermally-grown material; the fact that RTA is flux-grown may offer an advantage over KTP in terms of the eventual cost and size of available substrates. Karlsson, et al., recently demonstrated the feasibility of electric field poling in bulk RTA.³ We produced periodically-poled waveguides in RTA crystals grown from a pure arsenate solvent using our standard HTS growth method.⁴ The ionic conductivity, dielectric constant and loss were measured (22°C, 200 kHz) and had values of σ₃₃=3.2×10⁻⁸ S/cm, ε₃₃=19.7 and d₃₃=1.4×10⁻². The ferroelectric transition temperature was 810°C.

© 1996 Optical Society of America