Phase-transition-induced Thermal Hysteresis in Type-II Weyl Semimetals MoTe2 and Mo(1-x)W(x)Te2

Published

November 19, 2022

Author(s)

Md Sabbir Akhanda, Sergiy Krylyuk, Diane Dickie, Albert Davydov, Fei Han, Mingda Li, Mona Zebarjadi

Abstract

The resistivity versus temperature measurement is commonly used for identifying temperature-induced phase change and the resulting hysteresis loop. While the resistance is influenced by both the density of states and the carrier lifetimes, the Seebeck coefficient is influenced predominantly by the density of states, and hence is a better probe of the phase of the material. Here, 1T′ - Td temperature-induced phase transition in MoTe2 is studied using temperature-dependent X-ray diffraction, resistivity, and Seebeck coefficient measurements. A more distinct hysteresis is observed when measuring the Seebeck coefficient which is consistent with direct measurements of the crystallographic angle using the temperature-dependent X-ray diffraction. The Seebeck and electrical resistivity measurements indicate a competing contribution of the electrons and holes. The contribution of electron pockets becomes more dominant when molybdenum atoms are replaced by tungsten. In MoTe2, a topologically induced enhancement of the Nernst coefficient is observed at low temperatures, and a relatively large phase-transition induced Thomson coefficient of 111 μV⋅K- 1 is measured at 254 K which is larger than the Seebeck coefficient measured in the entire temperature range.

Citation

Materials Today Physics

Volume

29

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.mtphys.2022.100918

Local Download

Keywords

MoWTe2, phase transition, Seebeck coefficient

Citation

Akhanda, M. , Krylyuk, S. , Dickie, D. , Davydov, A. , Han, F. , Li, M. and Zebarjadi, M. (2022), Phase-transition-induced Thermal Hysteresis in Type-II Weyl Semimetals MoTe2 and Mo(1-x)W(x)Te2, Materials Today Physics, [online], https://doi.org/10.1016/j.mtphys.2022.100918, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935204 (Accessed March 13, 2025)