Restoring ergodicity in a strongly disordered interacting chain

• URL: http://arxiv.org/abs/2209.00661v2
• Date: Wed, 11 Jan 2023 09:21:16 GMT
• Title: Restoring ergodicity in a strongly disordered interacting chain
• Authors: B. Krajewski, L. Vidmar, J. Bonca, M. Mierzejewski
• Abstract summary: We show that only a small fraction of the two-body interaction represents a true local perturbation to the Anderson insulator. This establishes a view that the strongly disordered system should be viewed as a weakly perturbed integrable model.
• Score: 0.0
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Abstract: We consider a chain of interacting fermions with random disorder that was intensively studied in the context of many-body localization. We show that only a small fraction of the two-body interaction represents a true local perturbation to the Anderson insulator. While this true perturbation is nonzero at any finite disorder strength W, it decreases with increasing W. This establishes a view that the strongly disordered system should be viewed as a weakly perturbed integrable model, i.e., a weakly perturbed Anderson insulator. As a consequence, the latter can hardly be distinguished from a strictly integrable system in finite-size calculations at large W. We then introduce a rescaled model in which the true perturbation is of the same order of magnitude as the other terms of the Hamiltonian, and show that the system remains ergodic at arbitrary large disorder.

Related papers

• Exact dynamics of quantum dissipative $XX$ models: Wannier-Stark localization in the fragmented operator space [49.1574468325115]
  We find an exceptional point at a critical dissipation strength that separates oscillating and non-oscillating decay. We also describe a different type of dissipation that leads to a single decay mode in the whole operator subspace.
  arXiv  Detail & Related papers  (2024-05-27T16:11:39Z)
• Localization effects in disordered quantum batteries [0.0]
  localization on the local charging of quantum batteries modeled by disordered spin systems is investigated. We adopt a low-energy demanding charging process driven by local fields only. Our results are experimentally feasible in scalable systems, such as in superconducting integrated circuits.
  arXiv  Detail & Related papers  (2023-06-22T18:54:45Z)
• Disorder-Induced Entanglement Phase Transitions in Non-Hermitian Systems with Skin Effects [20.88126933913389]
  We study the dynamics of a many-body state of free fermions in the paradigmatic Hatano-Nelson model with open boundaries. We find that the area-law behavior of the entanglement entropy in the pristine Hatano-Nelson model develops into a logarithmic scaling for small disorder strength.
  arXiv  Detail & Related papers  (2023-05-21T04:34:05Z)
• 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)
• Multifractality in the interacting disordered Tavis-Cummings model [0.0]
  We analyze the spectral and transport properties of the interacting disordered Tavis-Cummings model at half excitation filling. We find that the bipartite entanglement entropy grows logarithmically with time. We show that these effects are due to the combination of finite interactions and integrability of the model.
  arXiv  Detail & Related papers  (2023-02-28T16:31:12Z)
• Sunburst quantum Ising model under interaction quench: entanglement and role of initial state coherence [0.0]
  We study the non-equilibrium dynamics of an isolated bipartite quantum system under interaction quench. We show the importance of the role played by the coherence of the initial state in deciding the nature of thermalization.
  arXiv  Detail & Related papers  (2022-12-23T11:57:47Z)
• Simultaneous Transport Evolution for Minimax Equilibria on Measures [48.82838283786807]
  Min-max optimization problems arise in several key machine learning setups, including adversarial learning and generative modeling. In this work we focus instead in finding mixed equilibria, and consider the associated lifted problem in the space of probability measures. By adding entropic regularization, our main result establishes global convergence towards the global equilibrium.
  arXiv  Detail & Related papers  (2022-02-14T02:23:16Z)
• Krylov Localization and suppression of complexity [0.0]
  We investigate Krylov complexity for the case of interacting integrable models at finite size. We find that complexity saturation is suppressed as compared to chaotic systems. We demonstrate this behavior for an interacting integrable model, the XXZ spin chain.
  arXiv  Detail & Related papers  (2021-12-22T18:45:32Z)
• Spectrum of localized states in fermionic chains with defect and adiabatic charge pumping [68.8204255655161]
  We study the localized states of a generic quadratic fermionic chain with finite-range couplings. We analyze the robustness of the connection between bands against perturbations of the Hamiltonian.
  arXiv  Detail & Related papers  (2021-07-20T18:44:06Z)
• Localization-delocalization effects of a delocalizing dissipation on disordered XXZ spin chains [0.0]
  We show that there exist regimes for which the natural orbitals of the single-particle density matrix of the steady state are all localized in the presence of strong disorders. We show that the averaged steady-state occupation in the eigenbasis of the open system Hamiltonian could follow an exponential decay for intermediate disorder strength in the presence of weak interactions.
  arXiv  Detail & Related papers  (2021-03-31T04:38:35Z)
• Distributing entanglement with separable states: assessment of encoding and decoding imperfections [55.41644538483948]
  Entanglement can be distributed using a carrier which is always separable from the rest of the systems involved. We consider the effect of incoherent dynamics acting alongside imperfect unitary interactions. We show that entanglement gain is possible even with substantial unitary errors.
  arXiv  Detail & Related papers  (2020-02-11T15:25:19Z)

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.