Convergence to equilibrium under a random Hamiltonian.
@article{Brando2012ConvergenceTE, title={Convergence to equilibrium under a random Hamiltonian.}, author={Fernando G. S. L. Brand{\~a}o and Piotr {\'C}wikliński and Michal Horodecki and Paweł Horodecki and Jarek K. Korbicz and Marek Mozrzymas}, journal={Physical review. E, Statistical, nonlinear, and soft matter physics}, year={2012}, volume={86 3 Pt 1}, pages={ 031101 } }
We analyze equilibration times of subsystems of a larger system under a random total Hamiltonian, in which the basis of the Hamiltonian is drawn from the Haar measure. We obtain that the time of equilibration is of the order of the inverse of the arithmetic average of the Bohr frequencies. To compute the average over a random basis, we compute the inverse of a matrix of overlaps of operators which permute four systems. We first obtain results on such a matrix for a representation of an…
Figures from this paper
55 Citations
Subsystem dynamics under random Hamiltonian evolution
- Physics
- 2012
We study time evolution of a subsystem's density matrix under unitary evolution, generated by a sufficiently complex, say quantum chaotic, Hamiltonian, modeled by a random matrix. We exactly…
Entanglement Dynamics of Random GUE Hamiltonians
- Physics
- 2020
In this work, we consider a model of a subsystem interacting with a reservoir and study dynamics of entanglement assuming that the overall time-evolution is governed by non-integrable Hamiltonians.…
Thermalization under randomized local Hamiltonians
- Physics, Mathematics
- 2012
Recently, there have been significant new insights concerning the conditions under which closed systems equilibrate locally. The question of whether subsystems thermalize—if the equilibrium state is…
Typical response of quantum pure states
- Physics
- 2013
The response of a quantum system in a pure state to an external force is investigated by reconsidering the standard statistical approach to quantum dynamics in the light of the statistical…
Generic features of the dynamics of complex open quantum systems: statistical approach based on averages over the unitary group.
- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2013
This work obtains exact analytic expressions for a class of functions expressed as integrals over the Haar measure of the unitary group in d dimensions, allowing a detailed comparison of typical regular and chaotic systems with the help of concepts from random matrix theory.
Classical Lieb-Robinson Bound for Estimating Equilibration Timescales of Isolated Quantum Systems.
- PhysicsPhysical review letters
- 2019
A Lieb-Robinson bound is derived on the speed of propagation across the classical network, which allows us to estimate the timescale at which the quantum system equilibrates.
Numerical evidence for approximate consistency and Markovianity of some quantum histories in a class of finite closed spin systems.
- PhysicsPhysical review. E
- 2016
The conditions under which the unitary dynamics may be mapped onto pertinent classical stochastic processes are discussed, based on the notions of "consistency" and "Markovianity".
Equilibration Times in Closed Quantum Many-Body Systems
- Physics
- 2018
This chapter provides a comprehensive discussion of equilibration from a heuristic point of view, with a focus on providing an intuitive understanding and connecting the problem with general properties of interacting many-body systems.
Equilibration time scales in closed many-body quantum systems.
- Physics
- 2017
We show that the physical mechanism for the equilibration of closed quantum systems is dephasing, and identify the energy scales that determine the equilibration timescale of a given observable. For…
Thermal Pure States for Finite and Isolated Quantum Systems.
- PhysicsThe journal of physical chemistry. A
- 2017
A general methodology to generate quantum states according to the TRE statistic is introduced, and the sampling is employed to characterize the ensemble distribution of thermodynamic functions like the entropy, internal energy, and temperature.
References
SHOWING 1-10 OF 49 REFERENCES
Subsystem dynamics under random Hamiltonian evolution
- Physics
- 2012
We study time evolution of a subsystem's density matrix under unitary evolution, generated by a sufficiently complex, say quantum chaotic, Hamiltonian, modeled by a random matrix. We exactly…
From Quantum Dynamics to the Canonical Distribution: General Picture and a Rigorous Example
- Physics
- 1998
Derivation of the canonical (or Boltzmann) distribution based only on quantum dynamics is discussed. Consider a closed system which consists of a mutually interacting subsystem and a heat bath, and…
Thermalization under randomized local Hamiltonians
- Physics, Mathematics
- 2012
Recently, there have been significant new insights concerning the conditions under which closed systems equilibrate locally. The question of whether subsystems thermalize—if the equilibrium state is…
Quantum mechanical evolution towards thermal equilibrium.
- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2009
It is proved, with virtually full generality, that reaching equilibrium is a universal property of quantum systems: almost any subsystem in interaction with a large enough bath will reach an equilibrium state and remain close to it for almost all times.
Absence of thermalization in nonintegrable systems.
- PhysicsPhysical review letters
- 2011
It is found that even if reduced states equilibrate, they can have memory on the initial conditions even in certain models that are far from integrable, thereby contributing to a recent debate on integrability.
A quantum central limit theorem for non-equilibrium systems: exact local relaxation of correlated states
- Mathematics
- 2010
We prove that quantum many-body systems on a one-dimensional lattice locally relax to Gaussian states under non-equilibrium dynamics generated by a bosonic quadratic Hamiltonian. This is true for a…
Exact relaxation in a class of nonequilibrium quantum lattice systems.
- PhysicsPhysical review letters
- 2008
This work rigorously proves that the evolving state locally relaxes to a steady state with maximum entropy constrained by second moments--thus maximizing the entanglement.
Approach to thermal equilibrium of macroscopic quantum systems.
- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2010
It is shown that for "typical" Hamiltonians with given eigenvalues, all initial state vectors psi(0) evolve in such a way that psi(t) is in thermal equilibrium for most times t.
Dynamical evolution of quantum oscillators toward equilibrium.
- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2009
A pure quantum state of large number N of oscillators, interacting via harmonic coupling, evolves such that any small subsystem n<<N of the global state approaches equilibrium, and intraentanglement within the "system" oscillators is found to exist.
Quench dynamics in randomly generated extended quantum models
- Physics
- 2012
We analyze the thermalization properties and the validity of the eigenstate thermalization hypothesis in a generic class of quantum Hamiltonians where the quench parameter explicitly breaks a Z2…