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arXiv · 1006.1484

Interferometric distillation and determination of unknown two-qubit entanglement

S. -S. B. Lee·H. -S. Sim
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Abstract

We propose a scheme for both distilling and quantifying entanglement, applicable to individual copies of an arbitrary unknown two-qubit state. It is realized in a usual two-qubit interferometry with local filtering. Proper filtering operation for the maximal distillation of the state is achieved, by erasing single-qubit interference, and then the concurrence of the state is determined directly from the visibilities of two-qubit interference. We compare the scheme with full state tomography.

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S. -S. B. Lee, H. -S. Sim. 2010-06-08. Interferometric distillation and determination of unknown two-qubit entanglement. https://doi.org/10.1103/physreva.79.052336

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