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Related papers: Fractional Chern insulators in magic-angle twisted…

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Moir\'e flatbands with high Chern numbers (C>1) offer opportunities to study the fractional quantum anomalous Hall effects that go beyond the Landau level paradigm with C=1, which remain unexplored yet. Here, we target the novel topological…

The experimental discoveries of fractional quantum anomalous Hall effects under zero magnetic fields in both transition metal dichalcogenide and pentalayer graphene moir\'e superlattices have aroused significant research interest. In this…

Strongly Correlated Electrons · Physics 2024-09-24 Zhongqing Guo , Xin Lu , Bo Xie , Jianpeng Liu

The fractional quantum anomalous Hall effect has recently been experimentally observed in zero-field fractional Chern insulators (FCI). However, an outstanding challenge is the presence of a substantial longitudinal resistance $R_{xx}$ (a…

We propose a generalized composite fermion (CF) theory for fractional Chern insulators (FCIs) by adapting the quantum mechanics approach of CFs. The theoretical framework naturally produces an effective CF Hamiltonian and a wavefunction…

Strongly Correlated Electrons · Physics 2025-09-12 Hao Jin , Junren Shi

We investigate the many-body ground states in a family of fractionally-filled bands where the Berry curvature fluctuations can be tuned while maintaining ideal quantum geometry. We numerically find that the neutral gap of the fractional…

Strongly Correlated Electrons · Physics 2025-12-09 Jingtian Shi , Jennifer Cano , Nicolás Morales-Durán

A recent experiment observes a series of quantum spin Hall effects in transition metal dichalcogenide moir\'e MoTe$_2$ [K. Kang, et. al, Nature 628, 522-526 (2024)]. Among them, the vanishing Hall signal at the filling factor $\nu=3$…

Strongly Correlated Electrons · Physics 2025-02-20 Feng Chen , Wei-Wei Luo , Wei Zhu , D. N. Sheng

Motivated by the higher Chern bands of twisted graphene multilayers, we consider flat bands with arbitrary Chern number $C$ with ideal quantum geometry. While $C>1$ bands differ from Landau levels, we show that these bands host exact…

Mesoscale and Nanoscale Physics · Physics 2023-07-25 Junkai Dong , Patrick J. Ledwith , Eslam Khalaf , Jong Yeon Lee , Ashvin Vishwanath

Recent experiments observed fractional Chern insulators (FCI) in twisted bilayer MoTe$_2$ at zero magnetic field, yet even the single-particle model of this material is controversial, leading to unreliable predictions of the experimental…

Mesoscale and Nanoscale Physics · Physics 2024-08-15 Yujin Jia , Jiabin Yu , Jiaxuan Liu , Jonah Herzog-Arbeitman , Ziyue Qi , Nicolas Regnault , Hongming Weng , B. Andrei Bernevig , Quansheng Wu

We show that the flat bands in the chiral model of magic-angle twisted bilayer graphene remain exactly flat in the presence of a perpendicular magnetic field. This is shown by an exact mapping between the model and the lowest Landau level…

Strongly Correlated Electrons · Physics 2021-09-29 Yarden Sheffer , Ady Stern

We predict twisted double bilayer graphene to be a versatile platform for the realization of fractional Chern insulators readily targeted by tuning the gate potential and the twist angle. Remarkably, these topologically ordered states of…

Mesoscale and Nanoscale Physics · Physics 2021-01-18 Zhao Liu , Ahmed Abouelkomsan , Emil J. Bergholtz

The possibility of realizing lattice analogs of fractional quantum Hall (FQH) states, so-called fractional Chern insulators (FCIs), in nearly flat topological (Chern) bands has attracted a lot of recent interest. Here, we make the…

Strongly Correlated Electrons · Physics 2013-01-16 Zhao Liu , Emil J. Bergholtz

The understanding of fractional Chern insulators (FCIs) has been deeply guided by band topology and quantum geometry. Here, we introduce a real-space theoretical framework in which FCIs are understood in terms of composite bosons, local…

Strongly Correlated Electrons · Physics 2026-02-17 Guangyu Yu , Zheng Zhu

The rapid advances in the study of fractional Chern insulators (FCIs) raise a fundamental question: while initially discovered in flat Chern bands motivated by their topological equivalence to Landau levels, is single- particle band…

Strongly Correlated Electrons · Physics 2025-10-17 Hongyu Lu , Wang Yao

Fractional Chern insulators are theoretically predicted states of electronic matter with emergent topological order. They exhibit the same universal properties as the fractional quantum Hall effect, but dispose of the need to apply a strong…

Strongly Correlated Electrons · Physics 2014-05-08 Adolfo G. Grushin , Álvaro Gómez-León , Titus Neupert

The search for candidate materials for fractional Chern insulators (FCIs) has mainly focused on the topological and geometrical structures of single-particle Chern bands. However, there are inherent limitations in approaches that neglect…

Strongly Correlated Electrons · Physics 2025-12-29 Nobuyuki Okuma , Tomonari Mizoguchi

Recent experimental advances have uncovered fractional Chern insulator (FCI) states in twisted MoTe$_2$ (tMoTe$_2$) systems under zero magnetic field. Understanding the interaction effects on topological phases within realistic model…

Strongly Correlated Electrons · Physics 2026-02-03 Jialin Chen , Qiaoyi Li , Xiaoyu Wang , Wei Li

We show that bilayer graphene in the presence of a 2D superlattice potential provides a highly tunable setup that can realize a variety of flat band phenomena. We focus on two regimes: (i) topological flat bands with non-zero Chern numbers,…

Mesoscale and Nanoscale Physics · Physics 2023-06-16 Sayed Ali Akbar Ghorashi , Aaron Dunbrack , Ahmed Abouelkomsan , Jiacheng Sun , Xu Du , Jennifer Cano

We report the first numerical observation of composite fermion (CF) states in fractional Chern insulators (FCI) using exact diagonalization. The ruby lattice Chern insulator model for both fermions and bosons exhibits a clear signature of…

Strongly Correlated Electrons · Physics 2015-03-20 Tianhan Liu , C. Repellin , B. Andrei Bernevig , N. Regnault

The interplay between strong electron-electron interactions and band topology can lead to novel electronic states that spontaneously break symmetries. The discovery of flat bands in magic-angle twisted bilayer graphene (MATBG) with…

Magic-angle twisted bilayer graphene (MA-TBG) exhibits intriguing quantum phase transitions triggered by enhanced electron-electron interactions when its flat-bands are partially filled. However, the phases themselves and their connection…

Mesoscale and Nanoscale Physics · Physics 2021-04-14 Shuang Wu , Zhenyuan Zhang , K. Watanabe , T. Taniguchi , Eva Y. Andrei