Odd-integer quantum Hall states and giant spin susceptibility in p-type few-layer WSe2

TL;DR

This study reports the observation of unconventional odd-integer quantum Hall states and giant spin susceptibility in high-mobility p-type few-layer WSe2, highlighting strong exchange interactions and potential ferromagnetic phenomena.

Contribution

It demonstrates the emergence of odd-integer quantum Hall states and giant Zeeman splitting in p-type WSe2, revealing strong exchange effects and ferromagnetism in this material.

Findings

Observation of odd-integer quantum Hall states

Landau level crossing at ultra-low angles

Zeeman energy exceeds cyclotron energy by three times

Abstract

We fabricate high-mobility p-type few-layer WSe2 field-effect transistors and surprisingly observe a series of quantum Hall (QH) states following an unconventional sequence predominated by odd-integer states under a moderate strength magnetic field. By tilting the magnetic field, we discover Landau level (LL) crossing effects at ultra-low coincident angles, revealing that the Zeeman energy is about three times as large as the cyclotron energy near the valence band top at {\Gamma} valley. This result implies the significant roles played by the exchange interactions in p-type few-layer WSe2, in which itinerant or QH ferromagnetism likely occurs. Evidently, the {\Gamma} valley of few-layer WSe2 offers a unique platform with unusually heavy hole-carriers and a substantially enhanced g-factor for exploring strongly correlated phenomena.