Electrooptic Ferroelectric Na K NbO Films

We report on waveguiding and electrooptic proper- ties of epitaxial Na K NbO films grown by radio-frequency magnetron sputtering on Al O single crystal substrates. High optical waveguiding performance has been demonstrated in infrared and visible light. The in-plane electrooptic effect has been recorded in transmission using a transverse geometry. At dc fields, the effective linear electrooptic coefficient was determined to 28 pm/V, which is promising for modulator applications. Index Terms—Electrooptic effects, ferroelectric films, planar waveguides.