Valley-Coherent Quantum Anomalous Hall State in AB-Stacked Bilayers
Abstract
Moiré materials provide fertile ground for the correlated and topological quantum phenomena. Among them, the quantum anomalous Hall (QAH) effect, in which the Hall resistance is quantized even under zero magnetic field, is a direct manifestation of the intrinsic topological properties of a material and an appealing attribute for low-power electronics applications. The QAH effect has been observed in both graphene and transition metal dichalcogenide (TMD) moiré materials. It is thought to arise from the interaction-driven valley polarization of the narrow moiré bands. Here, we show that the newly discovered QAH state in AB-stacked MoTe2/WSe2 moiré bilayers is not valley polarized but valley coherent. The layer- and helicity-resolved optical spectroscopy measurement reveals that the QAH ground state possesses spontaneous spin (valley) polarization aligned (antialigned) in two TMD layers. In addition, saturation of the out-of-plane spin polarization in both layers occurs only under high magnetic fields, supporting a canted spin texture. Our results call for a new mechanism for the QAH effect and highlight the potential of TMD moiré materials with strong electronic correlations and spin-orbit interactions for exotic topological states.
- Publication Date:
- Research Org.:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); Gordon and Betty Moore Foundation; US Air Force Office of Scientific Research (AFOSR); National Science Foundation (NSF)
- OSTI Identifier:
- 2280710
- Alternate Identifier(s):
- OSTI ID: 2323395
- Grant/Contract Number:
- SC0019481; FWP-100459; AC02-76SF00515; FA9550-19-1-0390; DMR-1807810; GBMF11563; GBMF9462; NNCI-2025233
- Resource Type:
- Published Article
- Journal Name:
- Physical Review. X
- Additional Journal Information:
- Journal Name: Physical Review. X Journal Volume: 14 Journal Issue: 1; Journal ID: ISSN 2160-3308
- Publisher:
- American Physical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; excitons; magnetic order; magnetism; magneto-optics; topological materials; topological phases of matter; transport phenomena; valley degrees of freedom; 2-dimensional systems; transition metal dichalcogenides
Citation Formats
Tao, Zui, Shen, Bowen, Jiang, Shengwei, Li, Tingxin, Li, Lizhong, Ma, Liguo, Zhao, Wenjin, Hu, Jenny, Pistunova, Kateryna, Watanabe, Kenji, Taniguchi, Takashi, Heinz, Tony F., Mak, Kin Fai, and Shan, Jie. Valley-Coherent Quantum Anomalous Hall State in AB-Stacked MoTe 2 / W S e 2 Bilayers. United States: N. p., 2024.
Web. doi:10.1103/PhysRevX.14.011004.
Tao, Zui, Shen, Bowen, Jiang, Shengwei, Li, Tingxin, Li, Lizhong, Ma, Liguo, Zhao, Wenjin, Hu, Jenny, Pistunova, Kateryna, Watanabe, Kenji, Taniguchi, Takashi, Heinz, Tony F., Mak, Kin Fai, & Shan, Jie. Valley-Coherent Quantum Anomalous Hall State in AB-Stacked MoTe 2 / W S e 2 Bilayers. United States. https://doi.org/10.1103/PhysRevX.14.011004
Tao, Zui, Shen, Bowen, Jiang, Shengwei, Li, Tingxin, Li, Lizhong, Ma, Liguo, Zhao, Wenjin, Hu, Jenny, Pistunova, Kateryna, Watanabe, Kenji, Taniguchi, Takashi, Heinz, Tony F., Mak, Kin Fai, and Shan, Jie. Wed .
"Valley-Coherent Quantum Anomalous Hall State in AB-Stacked MoTe 2 / W S e 2 Bilayers". United States. https://doi.org/10.1103/PhysRevX.14.011004.
@article{osti_2280710,
title = {Valley-Coherent Quantum Anomalous Hall State in AB-Stacked MoTe 2 / W S e 2 Bilayers},
author = {Tao, Zui and Shen, Bowen and Jiang, Shengwei and Li, Tingxin and Li, Lizhong and Ma, Liguo and Zhao, Wenjin and Hu, Jenny and Pistunova, Kateryna and Watanabe, Kenji and Taniguchi, Takashi and Heinz, Tony F. and Mak, Kin Fai and Shan, Jie},
abstractNote = {Moiré materials provide fertile ground for the correlated and topological quantum phenomena. Among them, the quantum anomalous Hall (QAH) effect, in which the Hall resistance is quantized even under zero magnetic field, is a direct manifestation of the intrinsic topological properties of a material and an appealing attribute for low-power electronics applications. The QAH effect has been observed in both graphene and transition metal dichalcogenide (TMD) moiré materials. It is thought to arise from the interaction-driven valley polarization of the narrow moiré bands. Here, we show that the newly discovered QAH state in AB-stacked MoTe2/WSe2 moiré bilayers is not valley polarized but valley coherent. The layer- and helicity-resolved optical spectroscopy measurement reveals that the QAH ground state possesses spontaneous spin (valley) polarization aligned (antialigned) in two TMD layers. In addition, saturation of the out-of-plane spin polarization in both layers occurs only under high magnetic fields, supporting a canted spin texture. Our results call for a new mechanism for the QAH effect and highlight the potential of TMD moiré materials with strong electronic correlations and spin-orbit interactions for exotic topological states.},
doi = {10.1103/PhysRevX.14.011004},
journal = {Physical Review. X},
number = 1,
volume = 14,
place = {United States},
year = {Wed Jan 10 00:00:00 EST 2024},
month = {Wed Jan 10 00:00:00 EST 2024}
}
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Works referenced in this record:
Massive Dirac fermions in moiré superlattices: A route towards topological flat minibands and correlated topological insulators
journal, August 2022
- Su, Ying; Li, Heqiu; Zhang, Chuanwei
- Physical Review Research, Vol. 4, Issue 3
Light–valley interactions in 2D semiconductors
journal, July 2018
- Mak, Kin Fai; Xiao, Di; Shan, Jie
- Nature Photonics, Vol. 12, Issue 8
Topological Phases in AB-Stacked
MoTe 2 / WSe 2 Z 2
journal, July 2022
- Pan, Haining; Xie, Ming; Wu, Fengcheng
- Physical Review Letters, Vol. 129, Issue 5
Quantum Anomalous Hall Effect from Inverted Charge Transfer Gap
journal, May 2022
- Devakul, Trithep; Fu, Liang
- Physical Review X, Vol. 12, Issue 2
The Quantum Anomalous Hall Effect: Theory and Experiment
journal, March 2016
- Liu, Chao-Xing; Zhang, Shou-Cheng; Qi, Xiao-Liang
- Annual Review of Condensed Matter Physics, Vol. 7, Issue 1
Excitonic Chern insulator and kinetic ferromagnetism in a
MoTe 2 / WSe 2
journal, February 2023
- Dong, Zhihuan; Zhang, Ya-Hui
- Physical Review B, Vol. 107, Issue 8
Unconventional superconductivity in magic-angle graphene superlattices
journal, March 2018
- Cao, Yuan; Fatemi, Valla; Fang, Shiang
- Nature, Vol. 556, Issue 7699
Nearly flat Chern bands in moiré superlattices
journal, February 2019
- Zhang, Ya-Hui; Mao, Dan; Cao, Yuan
- Physical Review B, Vol. 99, Issue 7
Semiconductor moiré materials
journal, July 2022
- Mak, Kin Fai; Shan, Jie
- Nature Nanotechnology, Vol. 17, Issue 7
Intrinsic quantized anomalous Hall effect in a moiré heterostructure
journal, December 2019
- Serlin, M.; Tschirhart, C. L.; Polshyn, H.
- Science, Vol. 367, Issue 6480
Continuous Mott transition in semiconductor moiré superlattices
journal, September 2021
- Li, Tingxin; Jiang, Shengwei; Li, Lizhong
- Nature, Vol. 597, Issue 7876
Correlated Quantum Phenomena in the Strong Spin-Orbit Regime
journal, March 2014
- Witczak-Krempa, William; Chen, Gang; Kim, Yong Baek
- Annual Review of Condensed Matter Physics, Vol. 5, Issue 1
Charge-order-enhanced capacitance in semiconductor moiré superlattices
journal, August 2021
- Li, Tingxin; Zhu, Jiacheng; Tang, Yanhao
- Nature Nanotechnology, Vol. 16, Issue 10
Emergent ferromagnetism near three-quarters filling in twisted bilayer graphene
journal, July 2019
- Sharpe, Aaron L.; Fox, Eli J.; Barnard, Arthur W.
- Science, Vol. 365, Issue 6453
Fermi polaron-polaritons in charge-tunable atomically thin semiconductors
journal, October 2016
- Sidler, Meinrad; Back, Patrick; Cotlet, Ovidiu
- Nature Physics, Vol. 13, Issue 3
Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
journal, March 2013
- Chang, C. -Z.; Zhang, J.; Feng, X.
- Science, Vol. 340, Issue 6129
Spin and pseudospins in layered transition metal dichalcogenides
journal, April 2014
- Xu, Xiaodong; Yao, Wang; Xiao, Di
- Nature Physics, Vol. 10, Issue 5
Magic in twisted transition metal dichalcogenide bilayers
journal, November 2021
- Devakul, Trithep; Crépel, Valentin; Zhang, Yang
- Nature Communications, Vol. 12, Issue 1
Scale-Invariant Quantum Anomalous Hall Effect in Magnetic Topological Insulators beyond the Two-Dimensional Limit
journal, September 2014
- Kou, Xufeng; Guo, Shih-Ting; Fan, Yabin
- Physical Review Letters, Vol. 113, Issue 13
Moiré heterostructures as a condensed-matter quantum simulator
journal, February 2021
- Kennes, Dante M.; Claassen, Martin; Xian, Lede
- Nature Physics, Vol. 17, Issue 2
Quantum anomalous Hall effect from intertwined moiré bands
journal, December 2021
- Li, Tingxin; Jiang, Shengwei; Shen, Bowen
- Nature, Vol. 600, Issue 7890
Simulation of Hubbard model physics in WSe2/WS2 moiré superlattices
journal, March 2020
- Tang, Yanhao; Li, Lizhong; Li, Tingxin
- Nature, Vol. 579, Issue 7799
Tunable correlated Chern insulator and ferromagnetism in a moiré superlattice
journal, March 2020
- Chen, Guorui; Sharpe, Aaron L.; Fox, Eli J.
- Nature, Vol. 579, Issue 7797
Topological charge density waves at half-integer filling of a moiré superlattice
journal, December 2021
- Polshyn, H.; Zhang, Y.; Kumar, M. A.
- Nature Physics, Vol. 18, Issue 1
Observation of moiré excitons in WSe2/WS2 heterostructure superlattices
journal, February 2019
- Jin, Chenhao; Regan, Emma C.; Yan, Aiming
- Nature, Vol. 567, Issue 7746
Electrical switching of magnetic order in an orbital Chern insulator
journal, November 2020
- Polshyn, H.; Zhu, J.; Kumar, M. A.
- Nature, Vol. 588, Issue 7836
Quantum anomalous Hall effect and electric-field-induced topological phase transition in AB-stacked
MoTe 2 / WSe 2
journal, December 2022
- Chang, Yao-Wen; Chang, Yia-Chung
- Physical Review B, Vol. 106, Issue 24
Valley-Polarized Quantum Anomalous Hall State in Moiré Heterobilayers
journal, January 2022
- Xie, Ying-Ming; Zhang, Cheng-Ping; Hu, Jin-Xin
- Physical Review Letters, Vol. 128, Issue 2
Nematic Excitonic Insulator in Transition Metal Dichalcogenide Moiré Heterobilayers
journal, July 2023
- Xie, Ming; Pan, Haining; Wu, Fengcheng
- Physical Review Letters, Vol. 131, Issue 4
Topological Insulators in Twisted Transition Metal Dichalcogenide Homobilayers
journal, February 2019
- Wu, Fengcheng; Lovorn, Timothy; Tutuc, Emanuel
- Physical Review Letters, Vol. 122, Issue 8
Observation of Quantized Exciton Energies in Monolayer under a Strong Magnetic Field
journal, April 2020
- Wang, Tianmeng; Li, Zhipeng; Lu, Zhengguang
- Physical Review X, Vol. 10, Issue 2
Superconductivity and strong correlations in moiré flat bands
journal, May 2020
- Balents, Leon; Dean, Cory R.; Efetov, Dmitri K.
- Nature Physics, Vol. 16, Issue 7
Many-body theory of trion absorption features in two-dimensional semiconductors
journal, January 2017
- Efimkin, Dmitry K.; MacDonald, Allan H.
- Physical Review B, Vol. 95, Issue 3
Graphene bilayers with a twist
journal, November 2020
- Andrei, Eva Y.; MacDonald, Allan H.
- Nature Materials, Vol. 19, Issue 12
Spin-textured Chern bands in AB-stacked transition metal dichalcogenide bilayers
journal, September 2021
- Zhang, Yang; Devakul, Trithep; Fu, Liang
- Proceedings of the National Academy of Sciences, Vol. 118, Issue 36
Orbital magnetic states in moiré graphene systems
journal, April 2021
- Liu, Jianpeng; Dai, Xi
- Nature Reviews Physics, Vol. 3, Issue 5
Mechanism for Anomalous Hall Ferromagnetism in Twisted Bilayer Graphene
journal, April 2020
- Bultinck, Nick; Chatterjee, Shubhayu; Zaletel, Michael P.
- Physical Review Letters, Vol. 124, Issue 16
Ferromagnetism in Narrow Bands of Moiré Superlattices
journal, May 2020
- Repellin, Cécile; Dong, Zhihuan; Zhang, Ya-Hui
- Physical Review Letters, Vol. 124, Issue 18