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arXiv · 1009.3659

Disentanglement and Decoherence without dissipation at non-zero temperatures

G. W. Ford·R. F. O'Connell
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Abstract

Decoherence is well understood, in contrast to disentanglement. According to common lore, irreversible coupling to a dissipative environment is the mechanism for loss of entanglement. Here, we show that, on the contrary, disentanglement can in fact occur at large enough temperatures $T$ even for vanishingly small dissipation (as we have shown previously for decoherence). However, whereas the effect of $T$ on decoherence increases exponentially with time, the effect of $T$ on disentanglement is constant for all times, reflecting a fundamental difference between the two phenomena. Also, the possibility of disentanglement at a particular $T$ increases with decreasing initial entanglement.

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G. W. Ford, R. F. O'Connell. 2010-09-19. Disentanglement and Decoherence without dissipation at non-zero temperatures. https://doi.org/10.1088/0031-8949%2F82%2F03%2F038112

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