Propagation of Elliptically Polarized Light through Ordered Block Copolymers

The grain structure of an ordered block copolymer material affects its mechanical, electrical, and optical properties, and depolarized light scattering (DPLS) has proven to be a useful method for characterizing this grain structure. In this study, we obtain and analyze DPLS patterns from an ordered diblock copolymer/lithium salt mixture by propagating eight different types of elliptically polarized (EP) light through the sample and demonstrate that the patterns are consistent with the ellipsoidal grain model (EGM), which assumes that the sample consists of randomly oriented ellipsoidal grains with optic axes coincident with their shape axes. EP light probes a different population of grains in a sample than either linearly or circularly polarized light and thus may be useful for the characterization of samples with anisotropic grain orientation distributions.