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arXiv · 0709.2100

Real Time Evolution in Quantum Many-Body Systems With Unitary Perturbation Theory

A. Hackl·S. Kehrein
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Abstract

We develop a new 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 non-equilibrium spin dynamics.

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A. Hackl, S. Kehrein. 2008-08-26. Real Time Evolution in Quantum Many-Body Systems With Unitary Perturbation Theory. https://doi.org/10.1103/physrevb.78.092303

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