dorsal/arxiv
View SchemaEntanglement degradation of a two-mode squeezed vacuum in absorbing and amplifying optical fibers
| Authors | Stefan Scheel, Tomas Opatrny, Dirk-Gunnar Welsch |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0006026 |
| URL | https://arxiv.org/abs/quant-ph/0006026 |
| DOI | 10.1134/1.1405221 |
Abstract
Applying the recently developed formalism of quantum-state transformation at absorbing dielectric four-port devices [L.~Kn\"oll, S.~Scheel, E.~Schmidt, D.-G.~Welsch, and A.V.~Chizhov, Phys. Rev. A {\bf 59}, 4716 (1999)], we calculate the quantum state of the outgoing modes of a two-mode squeezed vacuum transmitted through optical fibers of given extinction coefficients. Using the Peres--Horodecki separability criterion for continuous variable systems [R.~Simon, Phys. Rev. Lett. {\bf 84}, 2726 (2000)], we compute the maximal length of transmission of a two-mode squeezed vacuum through an absorbing system for which the transmitted state is still inseparable. Further, we calculate the maximal gain for which inseparability can be observed in an amplifying setup. Finally, we estimate an upper bound of the entanglement preserved after transmission through an absorbing system. The results show that the characteristic length of entanglement degradation drastically decreases with increasing strength of squeezing.
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"abstract": "Applying the recently developed formalism of quantum-state transformation at\nabsorbing dielectric four-port devices [L.~Kn\\\"oll, S.~Scheel, E.~Schmidt,\nD.-G.~Welsch, and A.V.~Chizhov, Phys. Rev. A {\\bf 59}, 4716 (1999)], we\ncalculate the quantum state of the outgoing modes of a two-mode squeezed vacuum\ntransmitted through optical fibers of given extinction coefficients. Using the\nPeres--Horodecki separability criterion for continuous variable systems\n[R.~Simon, Phys. Rev. Lett. {\\bf 84}, 2726 (2000)], we compute the maximal\nlength of transmission of a two-mode squeezed vacuum through an absorbing\nsystem for which the transmitted state is still inseparable. Further, we\ncalculate the maximal gain for which inseparability can be observed in an\namplifying setup. Finally, we estimate an upper bound of the entanglement\npreserved after transmission through an absorbing system. The results show that\nthe characteristic length of entanglement degradation drastically decreases\nwith increasing strength of squeezing.",
"arxiv_id": "quant-ph/0006026",
"authors": [
"Stefan Scheel",
"Tomas Opatrny",
"Dirk-Gunnar Welsch"
],
"categories": [
"quant-ph"
],
"doi": "10.1134/1.1405221",
"title": "Entanglement degradation of a two-mode squeezed vacuum in absorbing and amplifying optical fibers",
"url": "https://arxiv.org/abs/quant-ph/0006026"
},
"schema_id": "dorsal/arxiv",
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