arXiv:quant-ph/0512007 · Physical Review A

Entanglement and dephasing of quantum dissipative systems

Tobias Stauber, F. Guinea

Published Apr 21, 2006• 18 citations

Abstract

The von Neumann entropy of various quantum dissipative models is calculated in order to discuss the entanglement properties of these systems. First, integrable quantum dissipative models are discussed, i.e., the quantum Brownian motion and the quantum harmonic oscillator. In the case of the free particle, the related entanglement of formation shows no nonanalyticity. In the case of the dissipative harmonic oscillator, there is a nonanalyticity at the transition of underdamped to overdamped oscillations. We argue that this might be a general property of dissipative systems. We show that similar features arise in the dissipative two-level system and study different regimes using sub-Ohmic, Ohmic, and super-Ohmic baths, within a scaling approach.

DOI: 10.1103/physreva.73.042110

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