Dynamical phase transitions in quantum spin models with antiferromagnetic long-range interactions

• URL: http://arxiv.org/abs/2106.05282v2
• Date: Mon, 20 Sep 2021 19:03:52 GMT
• Title: Dynamical phase transitions in quantum spin models with antiferromagnetic long-range interactions
• Authors: Jad C. Halimeh, Maarten Van Damme, Lingzhen Guo, Johannes Lang, Philipp Hauke
• Abstract summary: Anomalous cusps in the return rate are ubiquitous at small quenches within the ordered phase in the case of ferromagnetic long-range interactions. For quenches across the quantum critical point, textitregular cusps appear in the return rate and connect to the local order parameter changing sign.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: In recent years, dynamical phase transitions and out-of-equilibrium criticality have been at the forefront of ultracold gases and condensed matter research. Whereas universality and scaling are established topics in equilibrium quantum many-body physics, out-of-equilibrium extensions of such concepts still leave much to be desired. Using exact diagonalization and the time-dependent variational principle in uniform martrix product states, we calculate the time evolution of the local order parameter and Loschmidt return rate in transverse-field Ising chains with antiferromagnetic power law-decaying interactions, and map out the corresponding rich dynamical phase diagram. \textit{Anomalous} cusps in the return rate, which are ubiquitous at small quenches within the ordered phase in the case of ferromagnetic long-range interactions, are absent within the accessible timescales of our simulations in the antiferromagnetic case, showing that long-range interactions are not a sufficient condition for their appearance. We attribute this to much weaker domain-wall binding in the antiferromagnetic case. For quenches across the quantum critical point, \textit{regular} cusps appear in the return rate and connect to the local order parameter changing sign, indicating the concurrence of two major concepts of dynamical phase transitions. Our results consolidate conclusions of previous works that a necessary condition for the appearance of anomalous cusps in the return rate after quenches within the ordered phase is for topologically trivial local spin flips to be the energetically dominant excitations in the spectrum of the quench Hamiltonian. Our findings are readily accessible in modern trapped-ion setups, and we outline the associated experimental considerations.

Related papers

• Dynamics of inhomogeneous spin ensembles with all-to-all interactions: breaking permutational invariance [49.1574468325115]
  We investigate the consequences of introducing non-uniform initial conditions in the dynamics of spin ensembles characterized by all-to-all interactions. We find that the dynamics of the spin ensemble now spans a more expansive effective Hilbert space.
  arXiv  Detail & Related papers  (2023-09-19T16:44:14Z)
• Slow semiclassical dynamics of a two-dimensional Hubbard model in disorder-free potentials [77.34726150561087]
  We show that introduction of harmonic and spin-dependent linear potentials sufficiently validates fTWA for longer times. In particular, we focus on a finite two-dimensional system and show that at intermediate linear potential strength, the addition of a harmonic potential and spin dependence of the tilt, results in subdiffusive dynamics.
  arXiv  Detail & Related papers  (2022-10-03T16:51:25Z)
• Spreading of a local excitation in a Quantum Hierarchical Model [62.997667081978825]
  We study the dynamics of the quantum Dyson hierarchical model in its paramagnetic phase. An initial state made by a local excitation of the paramagnetic ground state is considered. A localization mechanism is found and the excitation remains close to its initial position at arbitrary times.
  arXiv  Detail & Related papers  (2022-07-14T10:05:20Z)
• Effects of critical correlations on quantum percolation in two dimensions [0.0]
  We consider a two-dimensional tight-binding model that interacts with a background of classical spins in thermal equilibrium. To capture the salient features of the classical transition, we focus on the strong coupling limit. We provide evidence that the classical phase transition might induce a delocalization-localization transition in the quantum system at certain energies.
  arXiv  Detail & Related papers  (2022-03-28T18:00:01Z)
• Rotating Majorana Zero Modes in a disk geometry [75.34254292381189]
  We study the manipulation of Majorana zero modes in a thin disk made from a $p$-wave superconductor. We analyze the second-order topological corner modes that arise when an in-plane magnetic field is applied. We show that oscillations persist even in the adiabatic phase because of a frequency independent coupling between zero modes and excited states.
  arXiv  Detail & Related papers  (2021-09-08T11:18:50Z)
• Superradiant phase transition in complex networks [62.997667081978825]
  We consider a superradiant phase transition problem for the Dicke-Ising model. We examine regular, random, and scale-free network structures.
  arXiv  Detail & Related papers  (2020-12-05T17:40:53Z)
• Determination of dynamical quantum phase transitions in strongly correlated many-body systems using Loschmidt cumulants [0.0]
  We use Loschmidt cumulants to determine the critical times of interacting quantum systems after a quench. Our work demonstrates that Loschmidt cumulants are a powerful tool to unravel the far-from-equilibrium dynamics of strongly correlated many-body systems.
  arXiv  Detail & Related papers  (2020-11-27T09:03:47Z)
• Spin Entanglement and Magnetic Competition via Long-range Interactions in Spinor Quantum Optical Lattices [62.997667081978825]
  We study the effects of cavity mediated long range magnetic interactions and optical lattices in ultracold matter. We find that global interactions modify the underlying magnetic character of the system while introducing competition scenarios. These allow new alternatives toward the design of robust mechanisms for quantum information purposes.
  arXiv  Detail & Related papers  (2020-11-16T08:03:44Z)
• Dynamical crossover in the transient quench dynamics of short-range transverse field Ising models [4.16271611433618]
  We study the transient regimes of non-equilibrium processes probed by single-site observables that is magnetization per site. The decay rates of time-dependent and single-site observables exhibit a dynamical crossover that separates two dynamical regions. Our results reveal that scaling law exponent in short times at the close vicinity of the dynamical crossover is significantly different than the one predicted by analytical theory.
  arXiv  Detail & Related papers  (2020-04-26T04:39:51Z)
• Anomalous dynamics in the ergodic side of the Many-Body Localization transition and the glassy phase of Directed Polymers in Random Media [11.278111020737132]
  We show the existence of a glass transition within the extended regime separating a metallic-like phase at small disorder. We relate the dynamical evolution in the glassy phase to the depinning transition of Directed Polymers. By comparing the quantum dynamics on loop-less Cayley trees and Random Regular Graphs we discuss the effect of loops.
  arXiv  Detail & Related papers  (2020-03-21T11:02:06Z)
• Correlation-induced steady states and limit cycles in driven dissipative quantum systems [0.0]
  We study a driven-dissipative model of spins one-half (qubits) on a lattice with nearest-neighbor interactions. We characterize the spatial structure of the correlations in the steady state, as well as their temporal dynamics.
  arXiv  Detail & Related papers  (2020-01-15T18:38:39Z)

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.