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arXiv · 0801.1611

On the origin of the Raman scattering in heavily boron-doped diamond

I. I. Vlasov·E. A. Ekimov·A. A. Basov·E. Goovaerts·A. V. Zoteev
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Abstract

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 ^{10}B-substitution, whereas shifts to lower frequency are observed for all bands upon ^{13}C-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.

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I. I. Vlasov, E. A. Ekimov, A. A. Basov, E. Goovaerts, A. V. Zoteev. 2008-01-10. On the origin of the Raman scattering in heavily boron-doped diamond. https://arxiv.org/abs/0801.1611

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