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arXiv · 1501.06321

Raman scattering investigation of large positive magnetoresistance material WTe$_2$

W. -D. Kong·S. -F. Wu·P. Richard·C. -S. Lian·J. -T. Wang·C. -L. Yang·Y. -G. Shi·H. Ding
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Abstract

We have performed polarized Raman scattering measurements on WTe$_2$, for which an extremely large positive magnetoresistance has been reported recently. We observe 5 A$_1$ phonon modes and 2 A$_2$ phonon modes out of 33 Raman active modes, with frequencies in good accordance with first-principles calculations. The angular dependence of the intensity of the peaks observed is consistent with the Raman tensors of the $C_{2v}$ point group symmetry attributed to WTe$_2$. Although the phonon spectra suggest neither strong electron-phonon nor spin-phonon coupling, the intensity of the A$_1$ phonon mode at 160.6 cm$^{-1}$ shows an unconventional decrease with temperature decreasing, for which the origin remains unclear.

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W. -D. Kong, S. -F. Wu, P. Richard, C. -S. Lian, J. -T. Wang, C. -L. Yang, Y. -G. Shi, H. Ding. 2015-02-15. Raman scattering investigation of large positive magnetoresistance material WTe$_2$. https://doi.org/10.1063/1.4913680

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