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arXiv · 1502.03095

Quantum bounds on heat transport through nanojunctions

Edward Taylor·Dvira Segal
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Abstract

We derive rigorous quantum mechanical bounds for the heat current through a nanojunction connecting two thermal baths at different temperatures. Based on exact sum rules, these bounds compliment the well-known quantum of thermal conductance $\kappa_Q \equiv \pi k^2_B T/6\hbar$, which provides a bound for low-temperature heat transport in all systems, but is saturated only for noninteracting transport. In contrast, our bounds are saturated at high temperatures---but still in the quantum regime---, even when interactions are very strong. We evaluate these bounds for harmonic and strongly anharmonic junction models and compare with numerical approaches.

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Edward Taylor, Dvira Segal. 2015-02-10. Quantum bounds on heat transport through nanojunctions. https://doi.org/10.1103/physrevlett.114.220401

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