Coexistence of ergodic and non-ergodic behavior and level spacing statistics in a one-dimensional model of a flat band superconductor

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Teeriaho, Meri, Linho, Ville-Vertti, Swaminathan, Koushik, Peotta, Sebastiano
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866912315311390720
author Teeriaho, Meri
Linho, Ville-Vertti
Swaminathan, Koushik
Peotta, Sebastiano
author_facet Teeriaho, Meri
Linho, Ville-Vertti
Swaminathan, Koushik
Peotta, Sebastiano
contents Motivated by recent studies of the projected dice lattice Hamiltonian [K. Swaminathan et al., Phys. Rev. Research 5, 043215 (2023)], we introduce the on-site/bond singlet (OBS) model, a one-dimensional model of a flat band superconductor, in order to better understand the quasiparticle localization and interesting coexistence of ergodic and non-ergodic behavior present in the former model. The OBS model is the sum of terms that have direct counterparts in the projected dice lattice Hamiltonian, each of which is parameterized by a coupling constant. Exact diagonalization reveals that the energy spectrum and non-equilibrium dynamics of the OBS model are essentially the same as that of the dice lattice for some values of the coupling constants. The quasiparticle localization and breaking of ergodicity manifest in a striking manner in the level spacing distribution. Its near Poissonian form provides evidence for the existence of local integrals of motion and establishes the OBS model as a non-trivial integrable generalization of the projected Creutz ladder Hamiltonian. These results show that level spacing statistics is a promising tool to study quasiparticle excitations in flat band superconductors.
format Preprint
id arxiv_https___arxiv_org_abs_2411_09196
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Coexistence of ergodic and non-ergodic behavior and level spacing statistics in a one-dimensional model of a flat band superconductor
Teeriaho, Meri
Linho, Ville-Vertti
Swaminathan, Koushik
Peotta, Sebastiano
Superconductivity
Disordered Systems and Neural Networks
Statistical Mechanics
Strongly Correlated Electrons
Motivated by recent studies of the projected dice lattice Hamiltonian [K. Swaminathan et al., Phys. Rev. Research 5, 043215 (2023)], we introduce the on-site/bond singlet (OBS) model, a one-dimensional model of a flat band superconductor, in order to better understand the quasiparticle localization and interesting coexistence of ergodic and non-ergodic behavior present in the former model. The OBS model is the sum of terms that have direct counterparts in the projected dice lattice Hamiltonian, each of which is parameterized by a coupling constant. Exact diagonalization reveals that the energy spectrum and non-equilibrium dynamics of the OBS model are essentially the same as that of the dice lattice for some values of the coupling constants. The quasiparticle localization and breaking of ergodicity manifest in a striking manner in the level spacing distribution. Its near Poissonian form provides evidence for the existence of local integrals of motion and establishes the OBS model as a non-trivial integrable generalization of the projected Creutz ladder Hamiltonian. These results show that level spacing statistics is a promising tool to study quasiparticle excitations in flat band superconductors.
title Coexistence of ergodic and non-ergodic behavior and level spacing statistics in a one-dimensional model of a flat band superconductor
topic Superconductivity
Disordered Systems and Neural Networks
Statistical Mechanics
Strongly Correlated Electrons
url https://arxiv.org/abs/2411.09196