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arXiv · 1203.2561

Microscopic model of a phononic refrigerator

Liliana Arrachea·Eduardo Mucciolo·Claudio Chamon·Rodrigo Capaz
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Abstract

We analyze a simple microscopic model to pump heat from a cold to a hot reservoir in a nanomechanical system. The model consists of a one-dimensional chain of masses and springs coupled to a back gate through which a time-dependent perturbation is applied. The action of the gate is to modulate the coupling of the masses to a substrate via additional springs that introduce a moving phononic barrier. We solve the problem numerically using non-equilibrium Green function techniques. For low driving frequencies and for sharp traveling barriers, we show that this microscopic model realizes a phonon refrigerator.

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Liliana Arrachea, Eduardo Mucciolo, Claudio Chamon, Rodrigo Capaz. 2012-11-05. Microscopic model of a phononic refrigerator. https://doi.org/10.1103/physrevb.86.125424

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