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arXiv · 1506.05108

Measuring Entanglement in a Photonic Embedding Quantum Simulator

Juan C. Loredo·Marcelo P. Almeida·Roberto Di Candia·Julen S. Pedernales·Jorge Casanova·Enrique Solano·Andrew G. White
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Abstract

Measuring entanglement is a demanding task that usually requires full tomography of a quantum system, involving a number of observables that grows exponentially with the number of parties. Recently, it was suggested that adding a single ancillary qubit would allow for the efficient measurement of concurrence, and indeed any entanglement monotone associated to antilinear operations. Here, we report on the experimental implementation of such a device---an embedding quantum simulator---in photonics, encoding the entangling dynamics of a bipartite system into a tripartite one. We show that bipartite concurrence can be efficiently extracted from the measurement of merely two observables, instead of fifteen, without full tomographic information.

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Juan C. Loredo, Marcelo P. Almeida, Roberto Di Candia, Julen S. Pedernales, Jorge Casanova, Enrique Solano, Andrew G. White. 2016-03-01. Measuring Entanglement in a Photonic Embedding Quantum Simulator. https://doi.org/10.1103/physrevlett.116.070503

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