First- and second-order Raman scattering from MoTe2 single crystal
- 113 Downloads
We report on Raman experiments performed on a MoTe2 single crystal. The system belongs to the wide family of transition metal dichalcogenides which includes several of the most interesting two-dimensional materials for both basic and applied physics. Measurements were performed in the standard basal plane configuration, by placing the ab plane of the crystal perpendicular to the wave vector k i of the incident beam to explore the in-plane vibrational modes, and in the edge plane configuration with k i perpendicular to the crystal c axis, thus mainly exciting out-of-plane modes. For both configurations we performed a polarization-dependent study of the first-order Raman components and detailed computation of the corresponding selection rules. We were thus able to provide a complete assignment of the observed first-order Raman peaks, in agreement with previous literature results. A thorough analysis of the second-order Raman bands, as observed in both basal and edge plane configurations, provides new information and allows a precise assignment of these spectral structures. In particular, we have observed and assigned Raman active modes of the M point of the Brillouin zone previously predicted by ab initio calculations but never previously measured.
- 26.D.O. Dumcenco, Y.C. Su, Y.P. Wang, K.Y. Chen, Y.S. Huang, C.H. Ho, K.K. Tiong, Chin. J. Phys. 49, 270 (2011) Google Scholar
- 31.P. Yu, M. Cardona, Fundamentals of semiconductors: physics and materials properties, 4th edn. (Springer Science & Business Media, Berlin, 2010) Google Scholar
- 32.C. Marini, B. Joseph, S. Caramazza, F. Capitani, M. Bendele, M. Mitrano, D. Chermisi, S. Mangialardo, B. Pal, M. Goyal, J. Phys.: Condens. Matter 26, 452201 (2014) Google Scholar