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.
@article{arxiv.1701.00512,
title = {Odd-integer quantum Hall states and giant spin susceptibility in p-type few-layer WSe2},
author = {Shuigang Xu and Junying Shen and Gen Long and Zefei Wu and Zhi-qiang Bao and Cheng-Cheng Liu and Xiao Xiao and Tianyi Han and Jiangxiazi Lin and Yingying Wu and Huanhuan Lu and Jianqiang Hou and Liheng An and Yuanwei Wang and Yuan Cai and K. M. Ho and Yuheng He and Rolf Lortz and Fan Zhang and Ning Wang},
journal= {arXiv preprint arXiv:1701.00512},
year = {2017}
}
Comments
To appear in Physical Review Letters, including the Supplemental Material