We report polarized and resonant Raman scattering of single-crystal boron carbide (B4 C) at high pressures. Significant intensity enhancements of 270 and 1086 cm-1 Raman bands of B4 C have been observed at quasihydrostatic pressures higher than ∼20GPa. The pressure-induced intensity change of the 1086 cm-1 band is mainly due to the resonance between excitation energy and electronic transition, whereas the intensity change of 270 cm -1 band is caused by the depolarization effect. Importantly, the first-order phase transition has not been found at high quasihydrostatic pressures and all the Raman intensity changes along with the corresponding high-pressure lattice distortion can be recovered during unloading.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2010 Feb 24|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics