OBSERVATION OF FERROELECTRIC 180-DEGREES DOMAINS BY MICROPHOTOMETRY OF HOLOGRAPHIC GRATINGS

Abstract

A new holographic observation technique for 180 degrees domains is demonstrated with a cerium-doped strontium barium niobate sample containing two antiparallel ferroelectric domains. The method relies on the fact that the phase shift of holographically written refractive-index gratings is pi/2 or -pi/2 with respect to the initial Light interference pattern depending on the orientation of the domains. As a consequence, readout of these gratings creates at the exit face of the sample new interference patterns shifted by 0 or pi with respect to the initial one. These patterns, providing an image of the domain structure, are observed by microscope.