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Entanglement generation in harmonic chains: tagging by squeezing

M. Paternostro·M. S. Kim·E. Park·J. Lee
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Abstract

We address the problem of spring-like coupling between bosons in an open chain configuration where the counter-rotating terms are explicitly included. We show that fruitful insight can be gained by decomposing the time-evolution operator of this problem into a pattern of linear-optics elements. This allows us to provide a clear picture of the effects of the counter-rotating terms in the important problem of long-haul entanglement distribution. The analytic control over the variance matrix of the state of the bosonic register allows us to track the dynamics of the entanglement. This helps in designing a global addressing scheme, complemented by a proper initialization of the register, which quantitatively improves the entanglement between the extremal oscillators in the chain, thus providing a strategy for feasible long distance entanglement distribution.

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M. Paternostro, M. S. Kim, E. Park, J. Lee. 2005-06-17. Entanglement generation in harmonic chains: tagging by squeezing. https://doi.org/10.1103/physreva.72.052307

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