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Title: Entanglement and dephasing of quantum dissipative systems

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.

Authors:
;  [1]
  1. Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid (Spain)
Publication Date:
OSTI Identifier:
20787070
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.042110; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; BROWNIAN MOVEMENT; ENTROPY; HARMONIC OSCILLATORS; OSCILLATIONS; PARTICLES; QUANTUM ENTANGLEMENT

Citation Formats

Stauber, T., and Guinea, F.. Entanglement and dephasing of quantum dissipative systems. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Stauber, T., & Guinea, F.. Entanglement and dephasing of quantum dissipative systems. United States. doi:10.1103/PHYSREVA.73.0.
Stauber, T., and Guinea, F.. Sat . "Entanglement and dephasing of quantum dissipative systems". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787070,
title = {Entanglement and dephasing of quantum dissipative systems},
author = {Stauber, T. and Guinea, F.},
abstractNote = {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.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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