2005/08/05 by Andrea Agliati, A. Agliati, M. Bondani +7 · 5 citations
Computer Science · Physics and Astronomy · #Quantum Information and Cryptography #Quantum optics and atomic interactions #Random lasers and scattering media #quant-ph
paper · pdf · doi:10.1088/1464-4266/7/12/031
published as J. Opt. B 7, 652 (2005). · 20 Pages, 16 Low Resolution Figs. Full Res version at http://qinf.fisica.unimi.it/~paris/pubs.html To appear on J. Opt. B
arxiv created 2005/08/05 · openalex publication_date 2005/11/22 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We address joint photodetection as a method for discriminating between the classical correlations of a thermal beam divided by a beam splitter and the quantum entanglement of a twin beam obtained by parametric down-conversion. We show that for intense beams of light the detection of the difference photocurrent may be used, in principle, in order to reveal entanglement, while the simple measurement of the correlation coefficient is not sufficient. We have experimentally measured the correlation coefficient and the variance of the difference photocurrent for several classical and quantum states. Results are in good agreement with theoretical predictions taking into account the extra noise in the generated fields that is due to the pump laser fluctuations.