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arXiv · 0812.3782

Distance dependence of entanglement generation via a bosonic heat bath

Thomas Zell·Friedemann Queisser·Rochus Klesse
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Abstract

Within a generalized Caldeira-Leggett model we analyze the conditions under which a bosonic heat bath can entangle two microscopic quantum systems at a distance $r$. We find that the attainable entanglement is extremely distance-sensitive. Significant entanglement can only be achieved if the systems are within a {\em microscopic} distance that is of order of the cut-off wavelength $λ$ of the system-bath interaction. At larger distances the maximal entanglement is exponentially suppressed with a decay length of order $λ$. We conclude that entanglement generation via a heat bath is not suitable for entangling remote objects.

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Thomas Zell, Friedemann Queisser, Rochus Klesse. 2009-04-16. Distance dependence of entanglement generation via a bosonic heat bath. https://doi.org/10.1103/physrevlett.102.160501

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