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High efficiency transfer of quantum information and multi-particle entanglement generation in translation invariant quantum chains

Martin B Plenio·Fernando L Semiao
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Abstract

We demonstrate that a translation invariant chain of interacting quantum systems can be used for high efficiency transfer of quantum entanglement and the generation of multi-particle entanglement over large distances and between arbitrary sites without the requirement of precise spatial or temporal control. The scheme is largely insensitive to disorder and random coupling strengths in the chain. We discuss harmonic oscillator systems both in the case of arbitrary Gaussian states and in situations when at most one excitation is in the system. The latter case which we prove to be equivalent to an xy-spin chain may be used to generate genuine multi particle entanglement. Such a 'quantum data bus' may prove useful in future solid state architectures for quantum information processing.

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Martin B Plenio, Fernando L Semiao. 2005-01-06. High efficiency transfer of quantum information and multi-particle entanglement generation in translation invariant quantum chains. https://doi.org/10.1088/1367-2630%2F7%2F1%2F073

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