Competition between excitonic insulators and quantum Hall states in correlated electron-hole bilayers
Abstract
Excitonic insulators represent a unique quantum phase of matter, providing a rich ground for studying exotic quantum bosonic states. Strongly coupled electron-hole bilayers, which host stable dipolar exciton fluids with an exciton density that can be adjusted electrostatically, offer an ideal platform to investigate correlated excitonic insulators. Based on electron-hole bilayers made of MoSe2/hBN/WSe2 heterostructures, here we study the behavior of excitonic insulators in a perpendicular magnetic field. We report the observation of excitonic quantum oscillations in both Coulomb drag signals and electrical resistance at low to medium magnetic fields. Under a strong magnetic field, we identify multiple quantum phase transitions between the excitonic insulator phase and the bilayer quantum Hall insulator phase. These findings underscore the interplay between the electron-hole interactions and Landau level quantization that opens new possibilities for exploring quantum phenomena in composite bosonic insulators.
Keywords
Cite
@article{arxiv.2501.18168,
title = {Competition between excitonic insulators and quantum Hall states in correlated electron-hole bilayers},
author = {Ruishi Qi and Qize Li and Zuocheng Zhang and Zhiyuan Cui and Bo Zou and Haleem Kim and Collin Sanborn and Sudi Chen and Jingxu Xie and Takashi Taniguchi and Kenji Watanabe and Michael F. Crommie and Allan H. MacDonald and Feng Wang},
journal= {arXiv preprint arXiv:2501.18168},
year = {2025}
}