Flat band and Planckian metal

Abstract

We discuss the recent extension of the Sachdev-Ye-Kitaev (SYK) microscopic model by Patel and Sachdev in arXiv:1906.03265, which demonstrates the characteristic features of the Khodel-Shaginyan fermion condensate -- the existence of the finite region of momenta, where the energy of electrons is exactly zero (the flat band). The microscopic derivation of the flat band in this interacting model supports the original idea of Khodel and Shaginyan based on the phenomenological approach. It also suggests that it is the flat band, which is responsible for the linear dependence of resistivity on temperature in "strange metals".

2 pages, 1 figure, accepted in JETP Letters

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Cited by in corpus (17)

• Planckian Dissipation in Metals
• Are Heavy Fermion Strange Metals Planckian?
• Gap generation and flat band catalysis in dice model with local interaction
• Topological polarization, dual invariants, and surface flat band in crystalline insulators
• Planckian relaxation delusion in metals
• Infinite bound states and $1/n$ energy spectrum induced by a Coulomb-like potential of type III in a flat band system
• Phase diagram and topological order in the modulated $XYZ$ chain with magnetic fields
• Infinite bound states and hydrogen atom-like energy spectrum induced by a flat band
• Proposed realization of critical regions in a one-dimensional flat band lattice with a quasi-periodic potential
• On Planckian limit for inelastic relaxation in metals
• A classical model for sub-Planckian thermal diffusivity in complex crystals
• Non-Fermi liquid behavior in the Sachdev-Ye-Kitaev model for a one dimensional incoherent semimetal
• Bound states in the continuum (BIC) protected by self-sustained potential barriers in a flat band system
• Strange metal phase of disordered magic-angle twisted bilayer graphene at low temperatures: from flatbands to weakly coupled Sachdev-Ye-Kitaev bundles
• Exact mobility line and mobility ring in the complex energy plane of a flat band lattice with a non-Hermitian quasiperiodic potential
• Transport properties of strongly correlated Fermi systems
• What can we learn from nonequilibrium response of a strange metal?