GROWTH-RING-SHAPED DOMAIN AND OPTICAL PATTERNS IN LITHIUM NIOBATE-TANTULATE CRYSTAL

Cutting Lithium Niobate Tantulate (LTN) crystal vertically to z axis, we found that on z section there exists concentric cyclic structure similar to the annual rings of tree. When fine focused beams passed through the polydomain or monodomain etched crystal along z axis, optical patterns will emerge on z section. The cause of forming optical patterns is discussed.