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arXiv · 1705.09146

Temperature independent band structure of WTe2 as observed from ARPES

S. Thirupathaiah·Rajveer Jha·Banabir Pal·J. S. Matias·P. Kumar Das·I. Vobornik·R. A. Ribeiro·D. D. Sarma
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Abstract

Extremely large magnetoresistance (XMR), observed in transition metal dichalcogendies, WTe$_2$, has attracted recently a great deal of research interests as it shows no sign of saturation up to the magnetic field as high as 60 T, in addition to the presence of type-II Weyl fermions. Currently, there has been a lot of discussion on the role of band structure changes on the temperature dependent XMR in this compound. In this contribution, we study the band structure of WTe$_2$ using angle-resolved photoemission spectroscopy (ARPES) and first-principle calculations to demonstrate that the temperature dependent band structure has no substantial effect on the temperature dependent XMR as our measurements do not show band structure changes on increasing the sample temperature between 20 and 130 K. We further observe an electronlike surface state, dispersing in such a way that it connects the top of bulk holelike band to the bottom of bulk electronlike band. Interestingly, similar to bulk states, the surface state is also mostly intact with the sample temperature. Our results provide invaluable information in shaping the mechanism of temperature dependent XMR in WTe$_2$.

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S. Thirupathaiah, Rajveer Jha, Banabir Pal, J. S. Matias, P. Kumar Das, I. Vobornik, R. A. Ribeiro, D. D. Sarma. 2017-06-15. Temperature independent band structure of WTe2 as observed from ARPES. https://doi.org/10.1103/physrevb.96.165149

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