Abstract
The optical anisotropy of in the 0.08–5.6 eV region is investigated by polarized reflectance measurements on single crystals, and by transmittance, reflectance, and ellipsometric measurements on oriented thin films. In the visible–near-uv spectral region the anisotropy is relatively mild, but a huge anisotropy is observed in the infrared. Here, the reflectance increases with decreasing frequency for both polraizations, consistent with metallic conductance both parallel and perpendicular to the ab plane. The c-axis plasma frequency is strikingly low, but there is strong damping which could originate from a continuum of low-energy interband transitions.
- Received 11 May 1988
DOI:https://doi.org/10.1103/PhysRevB.38.5077
©1988 American Physical Society