THIN LITHIUM NIOBATE SINGLE CRYSTAL FILM

摘要

PURPOSE: To obtain an optical waveguide of single crystals having high crystallinity, high confining efficiency, high power density and small optical transmission loss. ;CONSTITUTION: A pseudo-substrate layer 2 made of a thin lithium tantalate single crystal film having excellent crystal transferring characteristics is formed as a middle layer on a lithium niobate single crystal substrate 3 contg. an element other than Nb and Li, e.g. Ti, Cr, Fe, Ni, Nd, Mg or V and an optical waveguide layer 1 made of a thin lithium niobate single crystal film is grown on the layer 2 to obtain an optical waveguide having a three layered (LN-LT- LN) structure. The crystal lattices of the LN substrate, the thin LT film (pseudo-substrate layer) and the thin LN film (waveguide layer) along the a-axes is matched to each other.;COPYRIGHT: (C)1993,JPO&Japio