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arXiv · 1506.04509

Raman study of lattice dynamics in Weyl semimetal TaAs

H. W. Liu·P. Richard·Z. D. Song·L. X. Zhao·Z. Fang·G. -F. Chen·H. Ding
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Abstract

We report a polarized Raman study of Weyl semimetal TaAs. We observe all the optical phonons, with energies and symmetries consistent with our first-principles calculations. We detect additional excitations assigned to multiple-phonon excitations. These excitations are accompanied by broad peaks separated by 140~cm$^{-1}$ that are also most likely associated with multiple-phonon excitations. We also noticed a sizable B$_1$ component for the spectral background, for which the origin remains unclear.

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H. W. Liu, P. Richard, Z. D. Song, L. X. Zhao, Z. Fang, G. -F. Chen, H. Ding. 2015-06-15. Raman study of lattice dynamics in Weyl semimetal TaAs. https://doi.org/10.1103/physrevb.92.064302

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