English
Related papers

Related papers: Topological flat band models with arbitrary Chern …

200 papers

Isolated flat bands with significantly quenched kinetic energy of electrons could give rise to exotic strongly correlated states from electron-electron interactions. More intriguingly, the interplay between topology and flat bands can…

Mesoscale and Nanoscale Physics · Physics 2024-08-19 Huaiqiang Wang , Yiliang Fan , Haijun Zhang

Recently, two-dimensional band insulators with a topologically nontrivial (almost) flat band has been studied extensively, which can realize integer and fractional quantum Hall effect in a system without an orbital magnetic field. Realizing…

Strongly Correlated Electrons · Physics 2013-02-20 Chao-Ming Jian , Zheng-Cheng Gu , Xiao-Liang Qi

Fractional Chern insulators (FCIs) are lattice analogues of fractional quantum Hall states that may provide a new avenue toward manipulating non-abelian excitations. Early theoretical studies have predicted their existence in systems with…

In a multiband Hubbard model the self-consistency relations for the two-body bound-state bands are in the form of a nonlinear eigenvalue problem. Assuming that the resultant eigenvectors form an orthonormal set, e.g., in the strong-binding…

Quantum Gases · Physics 2023-06-02 M. Iskin

We study four different models of Chern insulators in the presence of strong electronic repulsion at partial fillings. We observe that all cases exhibit a Laughlin-like phase at filling fraction 1/3. We provide evidence of such a strongly…

Strongly Correlated Electrons · Physics 2012-08-30 Yang-Le Wu , B. Andrei Bernevig , N. Regnault

Recently, fractional quantum anomalous Hall effects have been discovered in two-dimensional moir\'{e} materials when a topologically nontrivial band with Chern number $\mathcal{C}=1$ is partially doped. Remarkably, superlattice Bloch bands…

Mesoscale and Nanoscale Physics · Physics 2025-07-30 Vo Tien Phong , Cyprian Lewandowski

We address the question of whether fractionally filled bands with a nontrivial Chern index in zero external field could also exhibit a Fractional Quantum Hall Effect (FQHE). Numerical works suggest this is possible. Analytic treatments are…

Strongly Correlated Electrons · Physics 2011-09-13 Ganpathy Murthy , R. Shankar

We show a tight-binding model for double perovskite monolayers grown in the {001} crystallographic direction can exhibit higher Chern numbers for the lowest band of the model dispersion in the absence of an applied magnetic field, including…

Strongly Correlated Electrons · Physics 2016-11-28 A. M. Cook

In this study, a tight-binding model on square octagon lattice with nearest-neighbour and next-nearest-neighbour hoppings is considered. The system is topologically trivial although it exhibits quadratic band-touching points in its…

Mesoscale and Nanoscale Physics · Physics 2020-01-06 Arghya Sil , Asim Kumar Ghosh

We report the discovery of flatten Bloch bands with nontrivial topological numbers in a quasi-one-dimensional sawtooth chain. We present the nearly flat-band with a obvious gap and nonzero Chern number of the modulated sawtooth chain by…

Strongly Correlated Electrons · Physics 2013-11-19 Zhihao Xu , Linhu Li

In the search of fractional quantum anomalous Hall (FQAH) effect, the conventional wisdom is to start from a flat Chern band isolated from the rest of the Hilbert space by band gaps, so that many-body interaction can be projected to a…

Mesoscale and Nanoscale Physics · Physics 2025-05-13 Wenqi Yang , Dawei Zhai , Tixuan Tan , Feng-Ren Fan , Zuzhang Lin , Wang Yao

We study trilayer graphene arranged in a staircase stacking configuration with equal consecutive twist angle. On top of the moir\'e cristalline pattern, a supermoir\'e long-wavelength modulation emerges that we treat adiabatically. For each…

Mesoscale and Nanoscale Physics · Physics 2023-05-08 Daniele Guerci , Yuncheng Mao , Christophe Mora

We study the stability of composite fermion fractional quantum Hall states in Harper-Hofstadter bands with Chern number $|C|>1$. We analyze the states of the composite fermion series for bosons with contact interactions and (spinless)…

Strongly Correlated Electrons · Physics 2018-01-31 Bartholomew Andrews , Gunnar Möller

Recent experimental discovery of fractional Chern insulators at zero magnetic field in moir\'e superlattices has sparked intense interests in bringing Landau level physics to flat Chern bands. In twisted MoTe$_2$ bilayers (tMoTe$_2$),…

Strongly Correlated Electrons · Physics 2025-02-25 Chong Wang , Xiao-Wei Zhang , Xiaoyu Liu , Jie Wang , Ting Cao , Di Xiao

We study Chern numbers to characterize the ground state of strongly interacting systems on a lattice. This method allows us to perform a numerical characterization of bosonic fractional quantum Hall (FQH) states on a lattice where…

Mesoscale and Nanoscale Physics · Physics 2007-12-17 Mohammad Hafezi , Anders S. Sorensen , Mikhail D. Lukin , Eugene Demler

We prove that invisible bands associated with zeros of the single-particle Green's function exist ubiquitously at topological interfaces of 2D Chern insulators, dual to the chiral edge/domain-wall modes. We verify this statement in a…

Strongly Correlated Electrons · Physics 2023-09-19 Youjiang Xu , Irakli Titvinidze , Walter Hofstetter

Topological flat bands at the Fermi level offer a promising platform to study a variety of intriguing correlated phase of matter. Here we present band engineering in the twisted orbital-active bilayers with spin-orbit coupling. The symmetry…

Mesoscale and Nanoscale Physics · Physics 2022-09-15 Huan Wang , Yadong Jiang , Zhaochen Liu , Jing Wang

We have studied extensively the band crossing patterns of the bulk entanglement spectrum (BES) for various lattice Chern insulators. We find that only partitions with dual symmetry can have either stable nodal-lines or nodal-points in the…

Strongly Correlated Electrons · Physics 2016-12-21 Dah-Wei Chiou , Hsien-Chung Kao , Feng-Li Lin

In topological bands, it is impossible to construct exponentially localized Wannier functions while preserving the symmetries. Instead, in quantum Hall systems, one can define an overcomplete basis of spatially localized coherent states. In…

Strongly Correlated Electrons · Physics 2026-02-17 Nobuyuki Okuma

We develop the topological band theory for systems described by non-Hermitian Hamiltonians, whose energy spectra are generally complex. After generalizing the notion of gapped band structures to the non-Hermitian case, we classify "gapped"…

Mesoscale and Nanoscale Physics · Physics 2018-04-11 Huitao Shen , Bo Zhen , Liang Fu