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arXiv · 0908.2076

How small can thermal machines be? The smallest possible refrigerator

Noah Linden·Sandu Popescu·Paul Skrzypczyk
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Abstract

We investigate the fundamental dimensional limits to thermodynamic machines. In particular we show that it is possible to construct self-contained refrigerators (i.e. not requiring external sources of work) consisting of only a small number of qubits and/or qutrits. We present three different models, consisting of two qubits, a qubit and a qutrit with nearest-neighbour interactions, and a single qutrit respectively. We then investigate fundamental limits to their performance; in particular we show that it is possible to cool towards absolute zero.

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Noah Linden, Sandu Popescu, Paul Skrzypczyk. 2010-08-31. How small can thermal machines be? The smallest possible refrigerator. https://doi.org/10.1103/physrevlett.105.130401

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