Phonon Anharmonicity in Bulk Td-MoTe2

Published

July 18, 2016

Author(s)

Albert Davydov, Sergiy Krylyuk, Irina Kalish, Ryan Beams, Patrick Vora

Abstract

We examine anharmonic contributions to the optical phonon frequency in bulk Td-MoTe2 phase through temperature-dependent Raman spectroscopy. At temperatures greater than 100 K we find that the optical phonon modes redshift linearly with temperature in agreement with the Gruneisen model. Below 100 K the phonon frequency exhibits nonlinear temperature dependence that arises from phonon-phonon scattering processes where optical phonons decay into multiple acoustic phonons. Furthermore, the highest frequency Raman modes show changes in intensity and linewidth near T~250 K that correlate well with the Td -> 1T' structural phase transition. These results demonstrate that phonon-phonon interactions dominate anharmonic contributions at low temperatures in bulk Td-MoTe2, an experimental regime that is currently of intense focus in efforts to understand Weyle semimetals.

Citation

Applied Physics Letters

Pub Type

Journals

Keywords

Weyle semimetal, 2D material, MoTe2, Raman spectroscopy

Citation

Davydov, A. , Krylyuk, S. , Kalish, I. , Beams, R. and Vora, P. (2016), Phonon Anharmonicity in Bulk Td-MoTe2, Applied Physics Letters (Accessed October 28, 2025)