English
Related papers

Related papers: Correlations and entanglement in flat band models …

200 papers

We show that all the bands of the Hofstadter model on the torus have an exactly flat dispersion and Berry curvature when a special system size is chosen. This result holds for any hopping and Chern number. Our analysis therefore provides a…

Strongly Correlated Electrons · Physics 2014-09-24 Thomas Scaffidi , Steven H. Simon

The Harper-Hofstadter model provides a fractal spectrum containing topological bands of any integer Chern number, $C$. We study the many-body physics that is realized by interacting particles occupying Harper-Hofstadter bands with $|C|>1$.…

Strongly Correlated Electrons · Physics 2015-09-28 Gunnar Möller , Nigel R. Cooper

We construct generalized Hofstadter models that possess "color-entangled" flat bands and study interacting many-body states in such bands. For a system with periodic boundary conditions and appropriate interactions, there exist gapped…

Strongly Correlated Electrons · Physics 2015-01-29 Ying-Hai Wu , J. K. Jain , Kai Sun

Motivated by recent experiments on correlated van der Waals materials, including twisted and rhombohedral graphene and twisted WSe$_2$, we perform an analytical and numerical study of the effects of strong on-site and short-range…

Strongly Correlated Electrons · Physics 2024-12-16 Patrick H. Wilhelm , Andreas M. Läuchli , Mathias S. Scheurer

We present a theoretical study of mapping between Chern bands and generalized Landau levels in twisted bilayer MoTe$_2$ ($t$MoTe$_2$), where fractional Chern insulators down to zero magnetic fields have been observed. We construct an exact…

Mesoscale and Nanoscale Physics · Physics 2025-03-18 Bohao Li , Fengcheng Wu

An interesting route to the realization of topological Chern bands in ultracold atomic gases is through the use of optical flux lattices. These models differ from the tight-binding real-space lattice models of Chern insulators that are…

Quantum Gases · Physics 2015-04-24 A. Sterdyniak , B. Andrei Bernevig , Nigel R. Cooper , N. Regnault

We study a spin pump on a two-leg ladder chain of the Rice--Mele model. To characterize the spin pump, we propose the Chern number for the many-body ground state of the entanglement Hamiltonian, which is referred to as the entanglement…

Mesoscale and Nanoscale Physics · Physics 2016-07-25 T. Fukui , Y. Hatsugai

Topological invariants in the band structure, such as Chern numbers, are crucial for the classification of topological matters and dictate the occurrence of exotic properties, yet their direct spectroscopic determination has been largely…

Bipartite entanglement measures are fantastic tools to investigate quantum phases of correlated electrons. Here, I analyze the entanglement spectrum of **gapped** two-leg quantum Heisenberg ladders on a periodic ribbon partitioned into two…

Strongly Correlated Electrons · Physics 2015-03-17 Didier Poilblanc

We present a pedagogical review of the physics of fractional Chern insulators with a particular focus on the connection to the fractional quantum Hall effect. While the latter conventionally arises in semiconductor heterostructures at low…

Strongly Correlated Electrons · Physics 2015-10-05 S. A. Parameswaran , R. Roy , S. L. Sondhi

Entanglement is the key resource for quantum technologies and is at the root of exciting many-body phenomena. However, quantifying the entanglement between two parts of a real-world quantum system is challenging when it interacts with its…

Quantum Physics · Physics 2023-03-22 Christian Carisch , Oded Zilberberg

Topological nontrivial bands can be realized via Rydberg-dressed neutral atoms. We propose a two-dimensional hard-core boson model with a topological ground enrgy at band on a honeycomb lattice, where the particle hopping is realized via…

Quantum Gases · Physics 2022-08-25 Yang Zhao , Xiao-Feng Shi

Narrow band electron systems are particularly likely to exhibit correlated many-body phases driven by interaction effects. Examples include magnetic materials, heavy fermion systems, and topological phases such as fractional quantum Hall…

Strongly Correlated Electrons · Physics 2016-07-19 Ching Hua Lee , Daniel P. Arovas , Ronny Thomale

We propose a two-spin quantum-mechanical model with applied magnetic fields acting on the Poincar\'e-Bloch sphere, to reveal a new class of topological energy bands with Chern number one half for each spin-1/2. The mechanism behind this…

Mesoscale and Nanoscale Physics · Physics 2023-02-07 Joel Hutchinson , Karyn Le Hur

We point out the possibility of nearly flat band with Chern number C=2 on the dice lattice in a simple nearest-neighbor tightbinding model. This lattice can be naturally formed by three adjacent $(111)$ layers of cubic lattice, which may be…

Strongly Correlated Electrons · Physics 2012-03-21 Fa Wang , Ying Ran

We study ``frustrated'' hopping models, in which at least one energy band, at the maximum or minimum of the spectrum, is dispersionless. The states of the flat band(s) can be represented in a basis which is fully localized, having support…

Strongly Correlated Electrons · Physics 2011-10-20 Doron L. Bergman , Congjun Wu , Leon Balents

We investigate topological phase transitions in Chern insulators within three-band models, focusing on the empty band and lowest band populated by spinless fermions. We consider Lieb and kagome lattices and notice phase transitions driven…

Strongly Correlated Electrons · Physics 2017-10-19 P. Potasz , B. Jaworowski , M. Kupczyński , M. Brzezińska , P. Kaczmarkiewicz , A. Wójs

Many of the important phases observed in twisted transition metal dichalcogenide homobilayers are driven by short-range interactions, which should be captured by a local tight binding description since no Wannier obstruction exists for…

Strongly Correlated Electrons · Physics 2024-10-02 Valentin Crépel , Andrew Millis

Dispersionless bands, such as Landau levels, serve as a good starting point for obtaining interesting correlated states when interactions are added. With this motivation in mind, we study a variety of dispersionless ("flat") band structures…

Strongly Correlated Electrons · Physics 2013-05-29 Dmitry Green , Luiz Santos , Claudio Chamon

We study flat bands in bipartite tight-binding networks with discrete translational invariance. Chiral flat bands with chiral symmetry eigenenergy E = 0 and host compact localized eigenstates for finite range hopping. For a bipartite…

Mesoscale and Nanoscale Physics · Physics 2017-10-18 Ajith Ramachandran , Alexei Andreanov , Sergej Flach