Eigenstate thermalization in spin-1/2 systems with SU(2) symmetry

• URL: http://arxiv.org/abs/2503.01846v1
• Date: Mon, 03 Mar 2025 18:59:58 GMT
• Title: Eigenstate thermalization in spin-1/2 systems with SU(2) symmetry
• Authors: Rohit Patil, Marcos Rigol,
• Abstract summary: We study the diagonal and off-diagonal matrix elements of observables in the eigenstates of the extended spin-1/2 Heisenberg chain.<n>We explore integrable and nonintegrable regimes, and consider observables that preserve the SU(2) symmetry of the Hamiltonian as well as observables that break it.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We study the diagonal and off-diagonal matrix elements of observables in the eigenstates of the extended spin-1/2 Heisenberg chain, which exhibits the non-Abelian SU(2) symmetry. We explore integrable and nonintegrable regimes, and consider observables that preserve the SU(2) symmetry of the Hamiltonian as well as observables that break it. We study in detail the low-frequency behavior of the off-diagonal matrix elements at and away from integrability. In the nonintegrable regime, we test the non-Abelian eigenstate thermalization hypothesis, paying special attention to the effect of the spin, which is the novel conserved quantity introduced by the SU(2) symmetry.

Related papers

• Symmetries, Conservation Laws and Entanglement in Non-Hermitian Fermionic Lattices [37.69303106863453]
  Non-Hermitian quantum many-body systems feature steady-state entanglement transitions driven by unitary dynamics and dissipation. We show that the steady state is obtained by filling single-particle right eigenstates with the largest imaginary part of the eigenvalue. We illustrate these principles in the Hatano-Nelson model with periodic boundary conditions and the non-Hermitian Su-Schrieffer-Heeger model.
  arXiv  Detail & Related papers  (2025-04-11T14:06:05Z)
• Symmetry breaking in chaotic many-body quantum systems at finite temperature [0.0]
  Recent work has shown that the entanglement of finite-temperature eigenstates in chaotic quantum many-body local Hamiltonians can be accurately described. We build upon this result to investigate the universal symmetry-breaking properties of such eigenstates.
  arXiv  Detail & Related papers  (2025-04-08T15:41:54Z)
• Long-range entanglement from spontaneous non-onsite symmetry breaking [3.3754780158324564]
  We show a frustration-free lattice model exhibiting SSB of a non-onsite symmetry. We analytically prove the two-fold ground-state degeneracy and the existence of a finite energy gap. Our work reveals the exotic features of SSB of non-onsite symmetries, which may lie beyond the framework of topological holography.
  arXiv  Detail & Related papers  (2024-11-07T18:59:51Z)
• Asymmetry Amplification by a Nonadiabatic Passage through a Critical Point [0.0]
  We generalize the Hamiltonian dynamics of the Painleve'-2 equation to the case with many degrees of freedom.<n>The evolution eventually leads to a highly asymmetric state, no matter how weak the symmetry breaking parameter of the Hamiltonian is.<n>This suggests a potential mechanism for strong asymmetry in the production of quasi-particles with nearly identical characteristics.
  arXiv  Detail & Related papers  (2024-08-28T16:06:56Z)
• Non-abelian symmetry-resolved entanglement entropy [1.433758865948252]
  We introduce a framework for symmetry-resolved entanglement entropy with a non-abelian symmetry group. We derive exact formulas for the average and the variance of the typical entanglement entropy for an ensemble of random pure states with fixed non-abelian charges. We show that, compared to the abelian case, new phenomena arise from the interplay of locality and non-abelian symmetry.
  arXiv  Detail & Related papers  (2024-05-01T16:06:48Z)
• Three perspectives on entropy dynamics in a non-Hermitian two-state system [41.94295877935867]
  entropy dynamics as an indicator of physical behavior in an open two-state system with balanced gain and loss is presented. We distinguish the perspective taken in utilizing the conventional framework of Hermitian-adjoint states from an approach that is based on biorthogonal-adjoint states and a third case based on an isospectral mapping.
  arXiv  Detail & Related papers  (2024-04-04T14:45:28Z)
• Symmetry-restricted quantum circuits are still well-behaved [45.89137831674385]
  We show that quantum circuits restricted by a symmetry inherit the properties of the whole special unitary group $SU(2n)$. It extends prior work on symmetric states to the operators and shows that the operator space follows the same structure as the state space.
  arXiv  Detail & Related papers  (2024-02-26T06:23:39Z)
• Emergence of non-Abelian SU(2) invariance in Abelian frustrated fermionic ladders [37.69303106863453]
  We consider a system of interacting spinless fermions on a two-leg triangular ladder with $pi/2$ magnetic flux per triangular plaquette. Microscopically, the system exhibits a U(1) symmetry corresponding to the conservation of total fermionic charge, and a discrete $mathbbZ$ symmetry. At the intersection of the three phases, the system features a critical point with an emergent SU(2) symmetry.
  arXiv  Detail & Related papers  (2023-05-11T15:57:27Z)
• Eigenstate thermalization hypothesis in two-dimensional XXZ model with or without SU(2) symmetry [0.0]
  We show that the eigenstate thermalization hypothesis is still valid within each subspace where the total spin is a good quantum number. Numerical analysis of the Hamiltonian eigenvalue spectrum and matrix elements of an observable in the Hamiltonian eigenstate basis supports that the two-dimensional XXZ model follows the eigenstate thermalization hypothesis.
  arXiv  Detail & Related papers  (2022-10-26T10:00:44Z)
• Chiral Dirac-like fermion in spin-orbit-free antiferromagnetic semimetals [21.85167942898987]
  Dirac semimetal is a phase of matter, whose elementary excitation is described by the relativistic Dirac equation. Inspired by the flavor symmetry in particle physics, we propose a massless Dirac-like equation yet linking two Weyl fields with the identical chirality. Our work reveals a counterpart of the flavor symmetry in magnetic electronic systems, leading to further possibilities of emergent phenomena in quantum materials.
  arXiv  Detail & Related papers  (2021-07-21T09:56:14Z)
• SYK meets non-Hermiticity II: measurement-induced phase transition [16.533265279392772]
  We analytically derive the effective action in the large-$N$ limit and show that an entanglement transition is caused by the symmetry breaking in the enlarged replica space. We also verify the large-$N$ critical exponents by numerically solving the Schwinger-Dyson equation.
  arXiv  Detail & Related papers  (2021-04-16T17:55:08Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.