Construction of interacting flat-band models by molecular-orbital representation: Correlation functions, energy gap, and entanglement
arXiv:2108.02414 · doi:10.1093/ptep/ptac015
Abstract
We calculate correlation functions of exactly-solvable one-dimensional flat-band models by utilizing the "molecular-orbital" representation. The models considered in this paper have a gapped ground state with flat-band being fully occupied, even in the presence of the interaction. In this class of models, the space spanned by the "molecular-orbitals" is the co-space of that spanned by the flat bands. Thanks to this property, the correlation functions are calculated by using the information of the molecular-orbitals rather than the explicit forms of the flat-band wave functions, which simplifies the calculations. As a demonstration, several one-dimensional models and their correlation functions are presented. We also calculate the entanglement entropy by using the correlation function.
17 pages, 6 figures
References in corpus (13)
- High temperature fractional quantum Hall states
- Fractional quantum Hall states at zero magnetic field
- Nearly-flat bands with nontrivial topology
- Fractional quantum Hall effect in the absence of Landau levels
- Flat bands and Wigner crystallization in the honeycomb optical lattice
- Bose condensation in flat bands
- Anderson localisation in tight-binding models with flat bands
- Superconductivity in repulsively interacting fermions on a diamond chain: flat-band induced pairing
- Multiple quantum scar states and emergent slow-thermalization in the flat-band system
- Flat band, spin-1 Dirac cone, and Hofstadter diagram in the fermionic square kagome model
- Flat bands in Weaire-Thorpe model and silicene
- Revisiting Flat bands and localization
- Mott Insulator-like Bose-Einstein Condensation in a Tight-Binding System of Interacting Bosons with a Flat Band
Cited by in corpus (4)
- Coupled topological flat and wide bands: Quasiparticle formation and destruction
- Interacting Topological Quantum Chemistry in 2D: Many-body Real Space Invariants
- Molecular-orbital representation with random U(1) variables
- Unconventional gapless semiconductor in an extended martini lattice in covalent honeycomb materials