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arXiv · 0910.5754

Environment-induced entanglement with a single photon

Malena Hor-Meyll·Adriana Auyuanet·Carolina Borges·Adriano Aragão·José Augusto Huguenin·Antonio Khoury·Luiz Davidovich
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Abstract

We propose an all-optical setup, which couples different degrees of freedom of a single photon, to investigate entanglement generation by a common environment. The two qubits are represented by the photon polarization and Hermite-Gauss transverse modes, while the environment corresponds to the photon path. For an initially two-qubit separable state, the increase of entanglement is analyzed, as the probability of an environment-induced transition ranges from zero to one. An entanglement witness that is invariant throughout the evolution of the system yields a direct measurement of the concurrence of the two-qubit state.

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Malena Hor-Meyll, Adriana Auyuanet, Carolina Borges, Adriano Aragão, José Augusto Huguenin, Antonio Khoury, Luiz Davidovich. 2009-10-29. Environment-induced entanglement with a single photon. https://doi.org/10.1103/physreva.80.042327

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