We have studied cubic boron arsenide (BAs) by Raman spectroscopy and first-principles simulations. The Raman T2 phonon involving B vibrations in natBAs shows a complex isotope two-mode behavior, not seen before in isotopically disordered materials. The majority isotope 11B phonon at 704 cm-1 obeys average isotopic mass dependence and mass disorder renormalization, whereas a band at 723 cm-1 stems from predominately 10B vibrations in natBAs. The observed lack of T2 LO-TO splitting in both natBAs and 11BAs and third- and fourth-order anharmonicity contributions compensating each other in the temperature dependence of the T2 phonon are among the other curious vibrational properties of BAs.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2014 Jan 28|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics