A combined experimental and theoretical study of the structural, electronic and vibrational properties of bulk and few-layer Td-WTe2

Jana MK, Singh A, Late DJ, Rajamathi CR, Biswas K, Felser C, Waghmare UV, Rao CNR (2015)

Publication Type: Journal article

Publication year: 2015

Journal

Journal of Physics: Condensed Matter Institute of Physics: Hybrid Open Access

Book Volume: 27

Article Number: 285401

Journal Issue: 28

DOI: 10.1088/0953-8984/27/28/285401

Abstract

The recent discovery of non-saturating giant positive magnetoresistance has aroused much interest in Td-WTe2. We have investigated structural, electronic and vibrational properties of bulk and few-layer Td-WTe2 experimentally and theoretically. Spin-orbit coupling is found to govern the semi-metallic character of Td-WTe2 and its structural link with the metallic 1 T form provides an understanding of its structural stability. There is a metal-to-insulator switch-over in the electrical conductivity and a change in the sign of the Seebeck coefficient around 373 K. Lattice vibrations of Td-WTe2 have been analyzed using first-principles calculations. Out of the 33 possible zone-center Raman active modes, five distinct Raman bands are observed around 112, 118, 134, 165 and 212 cm-1 in bulk Td-WTe2. Based on symmetry analysis and calculated Raman tensors, we assign the intense bands at 165 cm-1 and 212 cm-1 to the and modes, respectively. Most of the Raman bands stiffen with decreasing thickness, and the ratio of the integrated intensities of the to bands decreases in the few-layer sample, while all the bands soften in both the bulk and few-layer samples with increasing temperature.

Involved external institutions

Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) IN India (IN) Council for Scientific and Industrial Research (CSIR) IN India (IN) Max-Planck-Institut für Chemische Physik fester Stoffe (MPI CPfS) / Max Planck Institute for Chemical Physics of Solids DE Germany (DE)

How to cite

APA:

Jana, M.K., Singh, A., Late, D.J., Rajamathi, C.R., Biswas, K., Felser, C.,... Rao, C.N.R. (2015). A combined experimental and theoretical study of the structural, electronic and vibrational properties of bulk and few-layer Td-WTe2. Journal of Physics: Condensed Matter, 27(28). https://doi.org/10.1088/0953-8984/27/28/285401

MLA:

Jana, Manoj K., et al. "A combined experimental and theoretical study of the structural, electronic and vibrational properties of bulk and few-layer Td-WTe2." Journal of Physics: Condensed Matter 27.28 (2015).

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