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arXiv · 1510.05035

No energy transport without discord

Seth Lloyd·Zi-Wen Liu·Stefano Pirandola·Vazrik Chiloyan·Yongjie Hu·Samuel Huberman·Gang Chen
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Abstract

We show that without quantum correlations, energy cannot flow. The result follows from a simple theorem that shows that systems whose dynamics do not generate quantum discord are effectively non-interacting. We show that the rate of heat transfer between two quantum systems at different temperatures is directly proportional to the instantaneous rate of increase of diagonal/energetic discord between the systems. Consequently, nanoscale heat transfer experiments can be used to measure discord directly. We report the results of a measurement of the increase in discord due to nanoscale heat flow across an aluminum-sapphire interface and find it to be $4.28 \times 10^{24}$ ${\rm bits}\,{\rm m^{-2}}\,{\rm K^{-1}}\,{\rm s^{-1}}$.

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Seth Lloyd, Zi-Wen Liu, Stefano Pirandola, Vazrik Chiloyan, Yongjie Hu, Samuel Huberman, Gang Chen. 2015-10-16. No energy transport without discord. https://arxiv.org/abs/1510.05035

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