dorsal/arxiv
View SchemaExperimental Generation of Large Quadrature EPR Entanglement with a Self-Phase-Locked Type II OPO Below Threshold
| Authors | Julien Laurat, Thomas Coudreau, Gaelle Keller, Nicolas Treps, Claude Fabre |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0410081 |
| URL | https://arxiv.org/abs/quant-ph/0410081 |
| DOI | 10.1103/PhysRevA.71.022313 |
| Journal | Physical Review A 71 (2005) 022313 |
Abstract
We study theoretically and experimentally the quantum properties of a type II frequency degenerate optical parametric oscillator below threshold with a quarter-wave plate inserted inside the cavity which induces a linear coupling between the orthogonally polarized signal and idler fields. This original device provides a good insight into general properties of two-mode gaussian states, illustrated in terms of covariance matrix. We report on the experimental generation of two-mode squeezed vacuum on non-orthogonal quadratures depending on the plate angle. After a simple operation, the entanglement is maximized and put into standard form, \textit{i.e.} quantum correlations and anti-correlations on orthogonal quadratures. A half-sum of squeezed variances as low as $0.33 \pm 0.02$, well below the unit limit for inseparability, is obtained and the entanglement measured by the entropy of formation.
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"abstract": "We study theoretically and experimentally the quantum properties of a type II\nfrequency degenerate optical parametric oscillator below threshold with a\nquarter-wave plate inserted inside the cavity which induces a linear coupling\nbetween the orthogonally polarized signal and idler fields. This original\ndevice provides a good insight into general properties of two-mode gaussian\nstates, illustrated in terms of covariance matrix. We report on the\nexperimental generation of two-mode squeezed vacuum on non-orthogonal\nquadratures depending on the plate angle. After a simple operation, the\nentanglement is maximized and put into standard form, \\textit{i.e.} quantum\ncorrelations and anti-correlations on orthogonal quadratures. A half-sum of\nsqueezed variances as low as $0.33 \\pm 0.02$, well below the unit limit for\ninseparability, is obtained and the entanglement measured by the entropy of\nformation.",
"arxiv_id": "quant-ph/0410081",
"authors": [
"Julien Laurat",
"Thomas Coudreau",
"Gaelle Keller",
"Nicolas Treps",
"Claude Fabre"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.71.022313",
"journal_ref": "Physical Review A 71 (2005) 022313",
"title": "Experimental Generation of Large Quadrature EPR Entanglement with a Self-Phase-Locked Type II OPO Below Threshold",
"url": "https://arxiv.org/abs/quant-ph/0410081"
},
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