Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Normal metal - superconductor tunnel junction as a Brownian refrigerator   Thermal noise generated by a hot resistor (resistance $R$) can, under proper
conditions, catalyze heat removal from a cold normal metal (N) in contact with
a superconductor (S) via a tunnel barrier. Such a NIS junction acts as
Maxwell's demon, rectifying the heat flow. Upon reversal of the temperature
gradient between the resistor and the junction the heat fluxes are reversed:
this presents a regime which is not accessible in an ordinary voltage-biased
NIS structure. We obtain analytical results for the cooling performance in an
idealized high impedance environment, and perform numerical calculations for
general $R$. We conclude by assessing the experimental feasibility of the
proposed effect.

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The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: cmp-lg
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The categories of this paper are: nlin
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The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: econ
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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga