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arXiv · 1808.08816

Evidence of Coulomb interaction induced Lifshitz transition and robust hybrid Weyl semimetal in Td MoTe2

N. Xu·Z. W. Wang·A. Magrez·P. Bugnon·H. Berger·C. E. Matt·V. N. Strocov·N. C. Plumb·M. Radovic·E. Pomjakushina·K. Conder·J. H. Dil·J. Mesot·R. Yu·H. Ding·M. Shi
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Abstract

Using soft x-ray angle-resolved photoemission spectroscopy we probed the bulk electronic structure of Td MoTe2. We found that on-site Coulomb interaction leads to a Lifshitz transition, which is essential for a precise description of the electronic structure. A hybrid Weyl semimetal state with a pair of energy bands touching at both type-I and type-II Weyl nodes is indicated by comparing the experimental data with theoretical calculations. Unveiling the importance of Coulomb interaction opens up a new route to comprehend the unique properties of MoTe2, and is significant for understanding the interplay between correlation effects, strong spin-orbit coupling and superconductivity in this van der Waals material.

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N. Xu, Z. W. Wang, A. Magrez, P. Bugnon, H. Berger, C. E. Matt, V. N. Strocov, N. C. Plumb, M. Radovic, E. Pomjakushina, K. Conder, J. H. Dil, J. Mesot, R. Yu, H. Ding, M. Shi. 2018-08-27. Evidence of Coulomb interaction induced Lifshitz transition and robust hybrid Weyl semimetal in Td MoTe2. https://doi.org/10.1103/physrevlett.121.136401

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