Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: True thermal antenna with hyperbolic metamaterials   A thermal antenna is an electromagnetic source which emits in its
surrounding, a spatially coherent field in the infrared frequency range.
Usually, its emission pattern changes with the wavelength so that the heat flux
it radiates is weakly directive. Here, we show that a class of hyperbolic
materials, possesses a Brewster angle which is weakly dependent on the
wavelength, so that they can radiate like a true thermal antenna with a highly
directional heat flux. The realization of these sources could open a new avenue
in the field of thermal management in far-field regime.

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The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga