Enhanced Electro-Optic Property in ${\rm LiNbO}_{3}$ by Electric Field Domain Inversion

Change in the value of half-wave voltage of ${\rm LiNbO}_{3}$ ( $z$ -cut) before and after high electric field domain inversion at room temperature has been reported. For verification, a Mach–Zehnder interferometric setup is used and the voltage required for phase reversal of the fringe pattern is noted for single domain and domain inverted sample. The technique of the used domain inversion process is discussed and confirmation of the domain inversion is also done. As the half-wave voltage decreases after domain inversion, it may be assumed that the overall electro-optic property of ${\rm LiNbO}_{3}$ has been enhanced. This might possibly been caused by the internal field compensating the spontaneous polarization of the crystal.