2008/01/10 by И. И. Власов, Е. А. Екимов, Vlasov, I. I. +7
Earth and Planetary Sciences · Materials Science · Physics and Astronomy · #Diamond and Carbon-based Materials Research #FOS: Physical sciences #Force Microscopy Techniques and Applications #High-pressure geophysics and materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.0801.1611
openalex publication_date 2008/01/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Isotopic substitution of boron and carbon is applied for the identification of the vibrational modes of heavily boron-doped diamond synthesized by high-pressure high-temperature technique. None of the bands in the Raman spectra are shifting upon 10B-substitution, whereas shifts to lower frequency are observed for all bands upon 13C-substitution as compared to a sample with natural isotope abundancies. These isotopic substitution experiments exclude the hypothesis of boron dimer related normal modes and strongly support the assignment of the previously studied "500 cm-1" and "1230 cm-1" bands and two weak bands at 1003 cm-1 and 1070 cm-1 to perturbed diamond lattice phonons, revealing the phonon density of states. A second-order phonon spectrum at combination and overtone frequencies is also identified. A bulk plasmon related mechanism is proposed for the enhancement of the phonon density of states spectrum relative to the zone-center phonons.