Anisotropic focusing characteristics of microdomain structures within crystalline Sr↓(0.61)Ba↓(0.39)Nb↓(2)O↓(6): the crystal ball

摘要

We report the anisotropic focusing characteristics of a spherically configured region of microdomains that have been induced Within a cubic-shaped crystal of Ce-doped Sr↓(0.61)Ba↓(0.39)Nb↓(2)O↓(6). The internal spherical structure focuses extraordinary polarized light, but not ordinary polarized light. The spherical region, which is easily observed via scattering, is formed as the crystal cools after a repoling cycle through the Curie temperature, with an applied field. Analytic modeling of the thermal gradients that exist within the crystal during cooling reveals a small (<1℃) temperature difference between the central and the outside regions. The similarity in shape between these temperature profiles and the observed scattering region suggests a possible mechanism for the growth of this spherical microdomained structure. # 1997 Optical Society of America