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arXiv · 1705.07217

MoTe2 : An uncompensated semimetal with extremely large magnetoresistance

S. Thirupathaiah·Rajveer Jha·Banabir Pal·J. S. Matias·P. Kumar Das·P. K. Sivakumar·I. Vobornik·N. C. Plumb·M. Shi·R. A. Ribeiro·D. D. Sarma
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Abstract

Transition-metal dichalcogenides (WTe$_2$ and MoTe$_2$) have drawn much attention, recently, because of the nonsaturating extremely large magnetoresistance (XMR) observed in these compounds in addition to the predictions of likely type-II Weyl semimetals. Contrary to the topological insulators or Dirac semimetals where XMR is linearly dependent on the field, in WTe$_2$ and MoTe$_2$ the XMR is nonlinearly dependent on the field, suggesting an entirely different mechanism. Electron-hole compensation has been proposed as a mechanism of this nonsaturating XMR in WTe$_2$, while it is yet to be clear in the case of MoTe$_2$ which has an identical crystal structure of WTe$_2$ at low temperatures. In this paper, we report low-energy electronic structure and Fermi surface topology of MoTe$_2$ using angle-resolved photoemission spectrometry (ARPES) technique and first-principle calculations, and compare them with that of WTe$_2$ to understand the mechanism of XMR. Our measurements demonstrate that MoTe$_2$ is an uncompensated semimetal, contrary to WTe$_2$ in which compensated electron-hole pockets have been identified, ruling out the applicability of charge compensation theory for the nonsaturating XMR in MoTe$_2$. In this context, we also discuss the applicability of the existing other conjectures on the XMR of these compounds.

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S. Thirupathaiah, Rajveer Jha, Banabir Pal, J. S. Matias, P. Kumar Das, P. K. Sivakumar, I. Vobornik, N. C. Plumb, M. Shi, R. A. Ribeiro, D. D. Sarma. 2017-06-15. MoTe2 : An uncompensated semimetal with extremely large magnetoresistance. https://doi.org/10.1103/physrevb.95.241105

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