Abstract
At both the cubic-rhombohedral phase-transition temperature and the zero-gap temperature , anomalous increases in Raman intensities are observed in (for ) single crystals. These are attributed to Raman scattering enhanced by the softening of the TO phonon near and also allowed by enhanced interband-mixing effects near . These interband-mixing effects not only enhance the Raman intensity, but also increase .
- Received 31 August 1976
DOI:https://doi.org/10.1103/PhysRevLett.39.143
©1977 American Physical Society