STRUCTURAL INFLUENCE OF PROTON-EXCHANGE ON DOMAIN-INVERTED LITHIUM-NIOBATE REVEALED BY MEANS OF SELECTIVE ETCHING

Selective etching is used to study the influence of different proton-e xchange methods on the crystal structure of periodically domain-invert ed lithium niobate. The annealed proton-exchange method is shown to in terfere strongly with previously patterned domains. Also, a less commo n graded proton-exchange method is demonstrated that leaves the ferroe lectric domain structure intact.