Abstract

A phenomenological study of beam fanning in BaTiO₃:Cr was made using a collimated Ar-ion laser beam (2-mm diameter λ = 4880 Å). Four distinct cases were observed. When the beam was initially incident antiparallel to the +c axis it was split into two components which separated in the opposite directions within the plane of polarization. These beams became nearly perpendicular to the c axis within 5 mm of the entrance surface. In the case where the beam was initially incident along the +c axis strong, diffuse scattering was observed within the first 2 mm of the surface. In both cases no transmitted beam was observed. With the incident beam propagating and polarized perpendicular to the c axis, there was a transmitted beam as well as a weak beam that fanned toward the +c direction. However, with the polarization along the c axis two beams were observed, one bending in the +c direction and the other in the −c direction. The bending angle of the beam in the +c direction was greater than that of the beam that bent in the −c direction. The polarization dependence of this phenomenon suggests that beam fanning may be related to the photovoltaic effect.

© 1985 Optical Society of America