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arXiv · 1111.4557

Entanglement Concentration with Quantum Non Demolition Hamiltonians

Richard Tatham·Natalia Korolkova
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Abstract

We devise and examine two procrustean entanglement concentration schemes using Quantum Non- Demolition (QND) interaction Hamiltonians in the continuous variable regime, applicable for light, for atomic ensembles or in a hybrid setting. We thus expand the standard entanglement distillation toolbox to the use of a much more general, versatile and experimentally feasible interaction class. The first protocol uses Gaussian ancillary modes and a non-Gaussian post-measurement, the second a non-Gaussian ancillary mode and a Gaussian post-measurement. We explicitly calculate the density matrix elements of the non-Gaussian mixed states resulting from these protocols using an elegant Wigner-function based method in a numerically efficient manner. We then quantify the entanglement increase calculating the Logarithmic Negativity of the output state and discuss and compare the performance of the protocols.

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Richard Tatham, Natalia Korolkova. 2011-11-19. Entanglement Concentration with Quantum Non Demolition Hamiltonians. https://arxiv.org/abs/1111.4557

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