Properties of doped and undoped crystals of single domain KTiOAsO4

Abstract
Large single crystals of KTiOAsO4 (KTA) measuring up to 35×31×58 mm3 (along abc) are grown from the pure potassium arsenate self-fluxes and from the tungstate flux using the seeded high-temperature solution growth technique. Small amounts of Fe2O3, Sc2O3, or In2O3 (∼0.2–0.4 wt %) are added to the melt to promote single-domain formation in the flux-grown crystals. We report here the linear optical and nonlinear optical properties of these crystals. We observed an unusually strong optical birefringence increase with Fe2O3 dopant concentration [δ(nznx)∼0.017/wt % Fe]. This increase leads to a blue shift in the second-harmonic generation cutoff wavelength of as much as 37 nm for a ∼0.47 wt % Fe-dopant level in KTA.