Equilibrium and dynamical phase transitions in fully connected quantum
Ising model: Approximate energy eigenstates and critical time
- URL: http://arxiv.org/abs/2012.00561v1
- Date: Tue, 1 Dec 2020 15:09:45 GMT
- Title: Equilibrium and dynamical phase transitions in fully connected quantum
Ising model: Approximate energy eigenstates and critical time
- Authors: Arun Sehrawat, Chirag Srivastava, Ujjwal Sen
- Abstract summary: We study equilibrium and dynamical properties of the finite-size fully connected Ising model with a transverse field at the zero temperature.
For both the approximate and exact eigenstates, we compute the energy gap, concurrence, and geometric measure of quantum entanglement.
We observe a good match in the case of energy gap and geometric entanglement between the approximate and exact eigenstates.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We study equilibrium as well as dynamical properties of the finite-size fully
connected Ising model with a transverse field at the zero temperature. In
relation to the equilibrium, we present approximate ground and first excited
states that have large overlap -- except near the phase transition point --
with the exact energy eigenstates. For both the approximate and exact
eigenstates, we compute the energy gap, concurrence, and geometric measure of
quantum entanglement. We observe a good match in the case of energy gap and
geometric entanglement between the approximate and exact eigenstates. Whereas,
when the system size is large, the concurrence shows a nice agreement only in
the paramagnetic phase. In a quench dynamics, we study the time period and the
first critical time, which play important roles in the dynamical phase
transitions, based on a dynamical order parameter and the Loschmidt rate,
respectively. When all the spins are initially polarized in the direction of
their mutual interaction, both the time period and critical time diverges
logarithmically with the system size at the dynamical critical point. When all
the spins are initially in the direction of transverse field, both the time
period and critical time exhibit logarithmic or power-law divergences depending
on the final field strength. In the case of convergence, we provide estimates
for the finite-size scaling and converged value.
Related papers
- Information scrambling and entanglement dynamics in Floquet Time Crystals [49.1574468325115]
We study the dynamics of out-of-time-ordered correlators (OTOCs) and entanglement of entropy as measures of information propagation in disordered systems.
arXiv Detail & Related papers (2024-11-20T17:18:42Z) - Geometric phases along quantum trajectories [58.720142291102135]
We study the distribution function of geometric phases in monitored quantum systems.
For the single trajectory exhibiting no quantum jumps, a topological transition in the phase acquired after a cycle.
For the same parameters, the density matrix does not show any interference.
arXiv Detail & Related papers (2023-01-10T22:05:18Z) - Indication of critical scaling in time during the relaxation of an open
quantum system [34.82692226532414]
Phase transitions correspond to the singular behavior of physical systems in response to continuous control parameters like temperature or external fields.
Near continuous phase transitions, associated with the divergence of a correlation length, universal power-law scaling behavior with critical exponents independent of microscopic system details is found.
arXiv Detail & Related papers (2022-08-10T05:59:14Z) - 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) - Quantum chaos and thermalization in the two-mode Dicke model [77.34726150561087]
We discuss the onset of quantum chaos and thermalization in the two-mode Dicke model.
The two-mode Dicke model exhibits normal to superradiant quantum phase transition.
We show that the temporal fluctuations of the expectation value of the collective spin observable around its average are small and decrease with the effective system size.
arXiv Detail & Related papers (2022-07-08T11:16:29Z) - Photoinduced prethermal order parameter dynamics in the two-dimensional
large-$N$ Hubbard-Heisenberg model [77.34726150561087]
We study the microscopic dynamics of competing ordered phases in a two-dimensional correlated electron model.
We simulate the light-induced transition between two competing phases.
arXiv Detail & Related papers (2022-05-13T13:13:31Z) - Quantum coherence controls the nature of equilibration in coupled
chaotic systems [0.0]
Quantum coherence of the initial product states in the uncoupled eigenbasis can be viewed as a resource for equilibration and approach to thermalization.
Results are given for four distinct perturbation strength regimes, the ultra-weak, weak, intermediate, and strong regimes.
Maximally coherent initial states thermalize for any perturbation strength in spite of the fact that in the ultra-weak perturbative regime the underlying eigenstates of the system have a tensor product structure and are not at all thermal-like.
arXiv Detail & Related papers (2022-04-15T17:33:44Z) - Space of initial conditions and universality in nonequilibrium quantum
dynamics [0.0]
We study the one-dimensional ferromagnets in the regime of spontaneously broken symmetry.
We analyze the expectation value of local operators for the infinite-dimensional space of initial conditions of domain wall type.
arXiv Detail & Related papers (2022-02-25T10:53:27Z) - Observation of Time-Crystalline Eigenstate Order on a Quantum Processor [80.17270167652622]
Quantum-body systems display rich phase structure in their low-temperature equilibrium states.
We experimentally observe an eigenstate-ordered DTC on superconducting qubits.
Results establish a scalable approach to study non-equilibrium phases of matter on current quantum processors.
arXiv Detail & Related papers (2021-07-28T18:00:03Z) - Dynamical phase transitions in quantum spin models with
antiferromagnetic long-range interactions [0.0]
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.
arXiv Detail & Related papers (2021-06-09T18:00:01Z) - 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.