Potassium tantalate-niobate mixed crystal thin films for applications in nonlinear integrated optics

Potassium tantalate-niobate mixed crystal (KTN) thin films are promising candidates to meet the needs of integrated nonlinear optical devices for electro-optic and frequencyconversion applications. In this contribution we report on pulsed-laser-deposition growth of ferroelectric KTN films on MgO substrates. It is shown that highly-oriented KTN films are epitaxially grown as revealed by X-ray diffraction analysis. Moreover, the thermal annealing treatment can be further optimized to obtain optically smooth KTN films with RMS surface roughness as low as 1 nm.