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arXiv:0709.2100 · Physical Review B

Real time evolution in quantum many-body systems with unitary perturbation theory

Andreas Hackl, Stefan K. Kehrein

Published Sep 17, 2008• 66 citations
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Abstract

We develop an analytical method for solving real time evolution problems of quantum many-body systems. Our approach is a direct generalization of the well-known canonical perturbation theory for classical systems. Similar to canonical perturbation theory, secular terms are avoided in a systematic expansion and one obtains stable long-time behavior. These general ideas are illustrated by applying them to the spin-boson model and studying its nonequilibrium spin dynamics.

DOI
10.1103/physrevb.78.092303

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