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

References in corpus (1)

• General entanglement scaling laws from time evolution

Cited by in corpus (3)

• Evolution of entanglement after a local quench
• Evolution of a quantum spin system to its ground state: Role of entanglement and interaction symmetry
• Entanglement and its applications in systems with many degrees of freedom