# MoTe2 : An uncompensated semimetal with extremely large magnetoresistance

## TL;DR

This study reveals that MoTe2 is an uncompensated semimetal with large magnetoresistance, contrasting with WTe2, and suggests that charge compensation is not the mechanism behind MoTe2's XMR.

## Contribution

The paper provides the first detailed electronic structure and Fermi surface analysis of MoTe2, showing it is an uncompensated semimetal, challenging previous charge compensation explanations for XMR.

## Key findings

- MoTe2 is an uncompensated semimetal.
- Contrasts with WTe2, which is charge compensated.
- Charge compensation theory does not explain MoTe2's XMR.

## 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.