Thermalization through unitary evolution of pure states

Abstract

The unitary time evolution of a critical quantum spin chain with an impurity is calculated, and the entanglement evolution is shown. Moreover, we show that the reduced density matrix of a part of the chain evolves such that the fidelity of its spectrum is very high with respect to a state in thermal equilibrium. Hence, a thermal state occurs through unitary time evolution in a simple spin chain with impurity.

8 pages, 7 figures

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Cited by in corpus (7)

• Evolution of entanglement after a local quench
• Finite size effects in global quantum quenches: examples from free bosons in an harmonic trap and the one-dimensional Bose-Hubbard model
• Local temperature in quantum thermal states
• Evolution of a quantum spin system to its ground state: Role of entanglement and interaction symmetry
• Statistical distribution of components of energy eigenfunctions: from nearly-integrable to chaotic
• Correlations in eigenfunctions of quantum chaotic systems with sparse Hamiltonian matrices
• Entanglement and its applications in systems with many degrees of freedom