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Title: Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity

Abstract

We investigate the influence of environmental noise on polarization entangled light generated by parametric emission in a cavity. By adopting a recent separability criterion, we show that (i) self-stimulation may suppress the detrimental influence of noise on entanglement, but (ii) once it becomes effective, a noise-equipped classical model of parametric emission provides the same results of quantum theory with respect to the separability criterion. More generally we also show that, in the macroscopic limit, it is not possible to observe violations of local realism with measurements of finite order n-particle correlations only. These results provide a prototypical case of the emergence of macroscopic local realism in the presence of strong entanglement even in the absence of decoherence.

Authors:
;  [1]; ; ;  [2]
  1. Dipartimento di Fisica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin (Italy)
  2. Dipartimento di Fisica della Materia e Tecnologie Fisiche Avanzate, Universita di Messina Salita Sperone 31, I-98166 Messina (Italy)
Publication Date:
OSTI Identifier:
20979283
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.020101; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CORRELATIONS; EMISSION; NOISE; OPTICS; PHOTONS; POLARIZATION; QUANTUM ENTANGLEMENT; VISIBLE RADIATION

Citation Formats

Portolan, S., Rossi, F., Di Stefano, O., Savasta, S., and Girlanda, R. Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.020101.
Portolan, S., Rossi, F., Di Stefano, O., Savasta, S., & Girlanda, R. Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity. United States. doi:10.1103/PHYSREVA.73.020101.
Portolan, S., Rossi, F., Di Stefano, O., Savasta, S., and Girlanda, R. Wed . "Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity". United States. doi:10.1103/PHYSREVA.73.020101.
@article{osti_20979283,
title = {Decoherence-free emergence of macroscopic local realism for entangled photons in a cavity},
author = {Portolan, S. and Rossi, F. and Di Stefano, O. and Savasta, S. and Girlanda, R.},
abstractNote = {We investigate the influence of environmental noise on polarization entangled light generated by parametric emission in a cavity. By adopting a recent separability criterion, we show that (i) self-stimulation may suppress the detrimental influence of noise on entanglement, but (ii) once it becomes effective, a noise-equipped classical model of parametric emission provides the same results of quantum theory with respect to the separability criterion. More generally we also show that, in the macroscopic limit, it is not possible to observe violations of local realism with measurements of finite order n-particle correlations only. These results provide a prototypical case of the emergence of macroscopic local realism in the presence of strong entanglement even in the absence of decoherence.},
doi = {10.1103/PHYSREVA.73.020101},
journal = {Physical Review. A},
number = 2,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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