English
Related papers

Related papers: Exciton fractional Chern insulators in moir\'e het…

200 papers

The experimental discovery of fractional Chern insulators (FCIs) in rhombohedral pentalayer graphene twisted on hexagonal boron nitride (hBN) has preceded theoretical prediction. Supported by large-scale first principles relaxation…

Moir\'e flatbands, occurring, e.g., in twisted bilayer graphene at magic angles, have attracted ample interest due to their high degree of experimental tunability and the intriguing possibility of generating novel strongly interacting…

Mesoscale and Nanoscale Physics · Physics 2020-03-17 Ahmed Abouelkomsan , Zhao Liu , Emil J. Bergholtz

A Chern insulator (quantum anomalous Hall insulator) phase is demonstrated to exist in a typical semi-Dirac system, the TiO2/VO2 heterostructure. By combining first-principles calculations with Wannier-based tight-binding model, we…

Materials Science · Physics 2015-11-04 Huaqing Huang , Zhirong Liu , Hongbin Zhang , Wenhui Duan , David Vanderbilt

Integer and fractional quantum anomalous Hall (QAH) effects have been widely seen in moir\'e systems. Recently there is even observation of a time reversal invariant fractional quantum spin hall (FQSH) state at filling $n=3$ in twisted…

Strongly Correlated Electrons · Physics 2024-02-27 Ya-Hui Zhang

Transition--metal dichalcogenides (TMDs) uniquely combine topological electronic states realized without external magnetic fields with a strong optical response arising from long--lived excitons. Motivated by this confluence, we investigate…

Strongly Correlated Electrons · Physics 2026-04-28 Tianhong Lu , Luiz H. Santos

We review various features of interacting Abelian topological phases of matter in two spatial dimensions, placing particular emphasis on fractional Chern insulators (FCIs) and fractional topological insulators (FTIs). We highlight aspects…

Strongly Correlated Electrons · Physics 2015-11-17 Titus Neupert , Claudio Chamon , Thomas Iadecola , Luiz H. Santos , Christopher Mudry

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

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…

Excitons are the neutral quasiparticles that form when Coulomb interactions create bound states between electrons and holes. Due to their bosonic nature, excitons are expected to condense and exhibit superfluidity at sufficiently low…

Mesoscale and Nanoscale Physics · Physics 2024-09-04 Hong-Yi Xie , Pouyan Ghaemi , Matteo Mitrano , Bruno Uchoa

We propose searching for Chern insulators by depositing atomic layers of elements with large spin-orbit coupling (e.g., Bi) on the surface of a magnetic insulator. We argue that such systems will typically have isolated surface bands with…

Materials Science · Physics 2013-04-16 Kevin F. Garrity , David Vanderbilt

Recent theoretical works have demonstrated the realization of fractional quantum anomalous Hall states (also called fractional Chern insulators) in topological flat band lattice models without an external magnetic field. Such newly proposed…

Strongly Correlated Electrons · Physics 2013-11-13 Wei-Wei Luo , Wen-Chao Chen , Yi-Fei Wang , Chang-De Gong

A recent experiment has reported the first observation of a zero-field fractional Chern insulator (FCI) phase in twisted bilayer MoTe$_2$ moir\'e superlattices [Nature 622, 63-68 (2023)]. The experimental observation is at an unexpected…

Strongly Correlated Electrons · Physics 2024-04-09 Chong Wang , Xiao-Wei Zhang , Xiaoyu Liu , Yuchi He , Xiaodong Xu , Ying Ran , Ting Cao , Di Xiao

The recent progress in engineering topological band structures in optical-lattice systems makes it promising to study fractional Chern insulator states in these systems. Here we consider a realistic finite system of a few repulsively…

Quantum Gases · Physics 2022-03-23 Botao Wang , Xiao-Yu Dong , André Eckardt

Fractionally filled Chern bands with strong interactions may give rise to fractional Chern insulator (FCI) states, the zero-field analogue of the fractional quantum Hall effect. Recent experiments have demonstrated the existence of FCIs in…

Mesoscale and Nanoscale Physics · Physics 2024-08-15 Jiabin Yu , Jonah Herzog-Arbeitman , Minxuan Wang , Oskar Vafek , B. Andrei Bernevig , Nicolas Regnault

Strong Coulomb interactions can drive electrons to crystallize into a Wigner lattice. Achieving the bosonic analogue - a crystal of excitons - has remained elusive due to their short lifetimes and weaker interactions. Here, we report the…

The Chern insulator displays a quantized Hall effect without Landau levels. In a landmark paper in 1988, Haldane showed that a Chern insulator could be realized through complex next-nearest-neighbor hopping in a honeycomb lattice. Despite…

We perform an extensive exact diagonalization study of interaction driven insulators in spin- and valley-polarized moir\'{e} flat bands of twisted bilayer graphene aligned with its hexagonal boron nitride substrate. In addition to…

Strongly Correlated Electrons · Physics 2021-03-05 Patrick Wilhelm , Thomas C. Lang , Andreas M. Läuchli

Fractional Chern insulators (FCIs) showing a transport effect with fractionally quantized Hall plateaus emerging under zero magnetic field, provide a radically new opportunity to engineer topological quantum electronics. By construction of…

We devise local lattice models whose ground states are model fractional Chern insulators---Abelian and non-Abelian topologically ordered states characterized by exact ground state degeneracies at any finite size and infinite entanglement…

Strongly Correlated Electrons · Physics 2016-05-31 Jörg Behrmann , Zhao Liu , Emil J. Bergholtz

Chern insulators are band insulators exhibiting a nonzero Hall conductance but preserving the lattice translational symmetry. We conclusively show that a partially filled Chern insulator at 1/3 filling exhibits a fractional quantum Hall…

Strongly Correlated Electrons · Physics 2015-03-19 N. Regnault , B. Andrei Bernevig