Signatures of fractional quantum anomalous Hall states in twisted MoTe2

Jiaqi Cai, Eric Anderson, Chong Wang, Xiaowei Zhang, Xiaoyu Liu, William Holtzmann, Yinong Zhang, Fengren Fan, Takashi Taniguchi, Kenji Watanabe, Ying Ran, Ting Cao, Liang Fu, Di Xiao, Wang Yao and Xiaodong Xu ()
Additional contact information
Jiaqi Cai: University of Washington
Eric Anderson: University of Washington
Chong Wang: University of Washington
Xiaowei Zhang: University of Washington
Xiaoyu Liu: University of Washington
William Holtzmann: University of Washington
Yinong Zhang: University of Washington
Fengren Fan: University of Hong Kong
Takashi Taniguchi: National Institute for Materials Science
Kenji Watanabe: National Institute for Materials Science
Ying Ran: Boston College
Ting Cao: University of Washington
Liang Fu: Massachusetts Institute of Technology
Di Xiao: University of Washington
Wang Yao: University of Hong Kong
Xiaodong Xu: University of Washington

Nature, 2023, vol. 622, issue 7981, 63-68

Abstract: Abstract The interplay between spontaneous symmetry breaking and topology can result in exotic quantum states of matter. A celebrated example is the quantum anomalous Hall (QAH) state, which exhibits an integer quantum Hall effect at zero magnetic field owing to intrinsic ferromagnetism1–3. In the presence of strong electron–electron interactions, fractional QAH (FQAH) states at zero magnetic field can emerge4–8. These states could host fractional excitations, including non-Abelian anyons—crucial building blocks for topological quantum computation9. Here we report experimental signatures of FQAH states in a twisted molybdenum ditelluride (MoTe2) bilayer. Magnetic circular dichroism measurements reveal robust ferromagnetic states at fractionally hole-filled moiré minibands. Using trion photoluminescence as a sensor10, we obtain a Landau fan diagram showing linear shifts in carrier densities corresponding to filling factor v = −2/3 and v = −3/5 ferromagnetic states with applied magnetic field. These shifts match the Streda formula dispersion of FQAH states with fractionally quantized Hall conductance of $${\sigma }_{xy}=-\,\frac{2}{3}\frac{{e}^{2}}{h}$$ σ x y = − 2 3 e 2 h and $${\sigma }_{xy}=-\,\frac{3}{5}\frac{{e}^{2}}{h}$$ σ x y = − 3 5 e 2 h , respectively. Moreover, the v = −1 state exhibits a dispersion corresponding to Chern number −1, consistent with the predicted QAH state11–14. In comparison, several non-ferromagnetic states on the electron-doping side do not disperse, that is, they are trivial correlated insulators. The observed topological states can be electrically driven into topologically trivial states. Our findings provide evidence of the long-sought FQAH states, demonstrating MoTe2 moiré superlattices as a platform for exploring fractional excitations.

Date: 2023
References: Add references at CitEc
Citations: View citations in EconPapers (8)

Downloads: (external link)
https://www.nature.com/articles/s41586-023-06289-w Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:622:y:2023:i:7981:d:10.1038_s41586-023-06289-w

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-023-06289-w

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().