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arXiv · 1611.00149

Quantification of Concurrence via Weak Measurement

Mikko Tukiainen·Hirokazu Kobayashi·Yutaka Shikano
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Abstract

Since entanglement is not an observable per se, measuring its value in practice is a difficult task. Here we propose a protocol for quantifying a particular entanglement measure, namely concurrence, of an arbitrary two-qubit pure state via a single fixed measurement set-up by exploiting so-called weak measurements and the associated weak values together with the properties of the Laguerre-Gaussian modes. The virtue of our technique is that it is generally applicable for all two-qubit systems and does not involve simultaneous copies of the entangled state. We also propose an explicit optical implementation of the protocol.

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Mikko Tukiainen, Hirokazu Kobayashi, Yutaka Shikano. 2017-05-09. Quantification of Concurrence via Weak Measurement. https://doi.org/10.1103/physreva.95.052301

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