Theoretical possibilities for flat-band superconductivity

Abstract

One novel arena for designing superconductors with high $T_C$ is the flat-band systems. A basic idea is that flat bands, arising from quantum mechanical interference, give unique opportunities for enhancing $T_C$ with (i) many pair-scattering channels between the dispersive and flat bands, and (ii) an even more interesting situation when the flat band is topological and highly entangled. Here we compare two routes, which comprise a multi-band system with a flat band coexisting with dispersive ones, and a one-band case with a portion of the band being flat. Superconductivity can be induced in both cases when the flat band or portion is "incipient" (close to, but away from, the Fermi energy). Differences are, for the multi-band case, we can exploit large entanglement associated with topological states, while for the one-band case a transition between different (d and p) wave pairings can arise. These hint at some future directions.

6 pages, 5 figures, Proc. Int. Conf. "Superstripes 2019"

References in corpus (10)

• Iron-Based Superconductors: current status of materials and pairing mechanism
• Two-Orbital Model Explains the Higher Transition Temperature of the Single-Layer Hg-Cuprate Superconductor Compared to That of the La-Cuprate Superconductor
• Effective theory and emergent $SU(2)$ symmetry in the flat bands of attractive Hubbard models
• Superconductivity in repulsively interacting fermions on a diamond chain: flat-band induced pairing
• Possible Fano resonance for high Tc multi-gap superconductivity in p-Terphenyl doped by K at the Lifshitz transition
• New class of flat-band models on tetragonal and hexagonal lattices: Gapped versus crossing flat bands
• Enhanced critical temperature, pairing fluctuation effects, and BCS-BEC crossover in a two-band Fermi gas
• Fermi-Bose mixtures and BCS-BEC crossover in high-Tc superconductors
• Wide applicability of high $T_c$ pairing originating from coexisting wide and incipient narrow bands in quasi one dimension
• Possible high-$T_c$ superconductivity due to incipient narrow bands originating from hidden ladders in Ruddlesden-Popper compounds

Cited by in corpus (63)

• Possible high $T_c$ Superconductivity in La${}_3$Ni${}_2$O${}_7$ under High Pressure through Manifestation of a Nearly-Half-Filled Bilayer Hubbard Model
• Optical Spectral Weight, Phase Stiffness and Tc Bounds for Trivial and Topological Flat Band Superconductors
• Crystal Net Catalog of Model Flat Band Materials
• Flat band superconductivity in the square-octagon lattice
• Electronic structure of the putative room-temperature superconductor Pb${}_9$Cu(PO${}_4$)${}_6$O
• Correlated Electronic Structure and Incipient Flat Bands of the Kagome Superconductor CsCr3Sb5
• Correlation-induced magnetism in substrate-supported 2D metal-organic frameworks
• Interaction induced doublons and embedded topological subspace in a complete flat-band system
• Superconducting mechanism for the cuprate Ba${}_2$CuO${}_{3+\delta }$ based on a multiorbital Lieb lattice model
• Flat-Band Enhanced Antiferromagnetic Fluctuations and Superconductivity in Pressurized CsCr${}_3$Sb${}_5$
• Metal-insulator transition in infinitesimally weakly disordered flatbands
• Designing nickelate superconductors with $d^8$ configuration exploiting mixed-anion strategy
• An Amelioration for the Sign Problem: Adiabatic Quantum Monte Carlo
• Flat-band solutions in $D$-dimensional decorated diamond and pyrochlore lattices: Reduction to molecular problem
• Resonant pair-exchange scattering and BCS-BEC crossover in a system composed of dispersive and heavy incipient bands: a Feshbach analogy
• Heavy-fermions in frustrated Hund's metal with portions of incipient flat-bands
• Flat-band ratio and quantum metric in the superconductivity of modified Lieb lattices
• Majorana corner states on the dice lattice
• Quantum Metric in Step Response
• Optical imprinting of superlattices in two-dimensional materials
• Flat Band Induced Metal-Insulator Transitions for Weak Magnetic Flux and Spin-Orbit Disorder
• Engineering topological phases in triple HgTe/CdTe quantum wells
• Unconventional delocalization in a family of 3D Lieb lattices
• Going beyond the Chandrasekhar-Clogston limit in a flat-band superconductor
• Superconductivity enhanced by pair fluctuations between wide and narrow bands
• Nematicity-enhanced superconductivity in systems with a non-Fermi liquid behavior
• Flat Bands and Compact Localised States: A Carrollian roadmap
• Pairs, trimers and BCS-BEC crossover near a flat band: the sawtooth lattice
• Unconventional superconductivity near a flat band in organic and organometallic materials
• Flat bands and temperature-driven phase transition in quasi-one-dimensional zigzag chains
• Emergent Fano-Feshbach resonance in two-band superconductors with an incipient quasi-flat band: Enhanced critical temperature evading particle-hole fluctuations
• Exceeding the Chandrasekhar-Clogston limit in flat-band superconductors: A multiband strong-coupling approach
• Theoretical study of spin-fluctuation-mediated superconductivity in two-dimensional Hubbard models with an incipient flat band
• Programmable Hamiltonian engineering with quadratic quantum Fourier transform
• Electronic Correlation Effects on Stabilizing a Perfect Kagome Lattice and Ferromagnetic Fluctuation in LaRu${}_3$Si${}_2$
• Moiré semiconductors on twisted bilayer dice lattice
• Fubini-Study metric and topological properties of flat band electronic states: the case of an atomic chain with $s-p$ orbitals
• Compact Wannier Functions in One Dimension
• Designing single and degenerate flat bands in the kagome lattice with long-range hopping
• Construction of interacting flat-band models by molecular-orbital representation: Correlation functions, energy gap, and entanglement
• Flat bands without twists: periodic holey graphene
• Flat bands in condensed-matter systems -- perspective for magnetism and superconductivity
• Engineering flux-controlled flat bands and topological states in a Stagome lattice
• Trapping Hard-Core Bosons in Flatband Lattices
• BCS-BCS crossover between atomic and molecular superfluids in a Bose-Fermi mixture
• Superconductivity in Quantum Complex Matter: the Superstripes Landscape
• The interplay between a pseudogap and superconductivity in a two-dimensional Hubbard model
• Coexisting Kagome and Heavy Fermion Flat Bands in YbCr${}_6$Ge${}_6$
• Stoner ferromagnetism in a momentum-confined interacting 2D electron gas
• Evidence of Molecular Hydrogen in the N-doped LuH3 System: a Possible Path to Superconductivity?
• Unconventional gapless semiconductor in an extended martini lattice in covalent honeycomb materials
• Selective band interaction and long-range hopping in a structured environment with giant atoms
• Phase diagram of a coupled trimer system at half filling using the Hubbard model
• Hidden Pseudogap and Excitation Spectra in a Strongly Coupled Two-Band Superfluid/Superconductor
• Nonlinear compact localized modes in flux-dressed octagonal-diamond photonic lattice
• Proximity-induced flat bands and topological properties in a decorated diamond chain
• Flat bands and band touching from real-space topology in hyperbolic lattices
• Revisiting flat band superconductivity: dependence on minimal quantum metric and band touchings
• Enhanced Andreev Reflection in Flat-Band Systems: Wave Packet Dynamics, DC Transport and the Josephson Effect
• Three-dimensional flat bands and possible interlayer triplet pairing superconductivity in the alternating twisted NbSe${}_2$ moiré bulk
• Flux-induced strengthening of the magnetic couplings in a flat-band diamond chain
• Influence of flat bands on RKKY interaction: perspective of Fano defects
• RKKY couplings in the Lieb lattice: flat-band induced frustration