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arXiv · 2008.11733

Gaussian state entanglement witnessing through lossy compression

Waldemar Klobus·Pawel Cieslinski·Lukas Knips·Pawel Kurzynski·Wieslaw Laskowski
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Abstract

We propose a method to witness entanglement between two continuous-variable systems in a Gaussian state. Its key ingredient is a local lossy state transfer from the original spatially separated systems onto two spatially separated qubits. The qubits are initially in a pure product state, therefore by detecting entanglement between the qubits we witness entanglement between the two original systems. This method greatly simplifies entanglement witnessing in complex systems.

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Waldemar Klobus, Pawel Cieslinski, Lukas Knips, Pawel Kurzynski, Wieslaw Laskowski. 2020-08-26. Gaussian state entanglement witnessing through lossy compression. https://doi.org/10.1103/physreva.103.032412

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