Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low work function in the 122-family of iron-based superconductors   We determine the work functions of the iron arsenic compounds $A$Fe$_2$As$_2$
($A=\mathrm{Ca, Ba, Cs}$) using photoemission spectroscopy to be 2.7 eV for
CaFe$_2$As$_2$, 1.8 eV for BaFe$_2$As$_2$, and 1.3 eV for CsFe$_2$As$_2$. The
work functions of these 122 iron-based superconductors track those of the
elementary metal $A$ but are substantially smaller. The most likely explanation
of this observation is that the cleaving surface exposes only half an
$A$-layer. The low work function and good photoemission cross section of
BaFe$_2$As$_2$ and CsFe$_2$As$_2$ enable photoemission even from a common white
LED light.

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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
10
The categories of this paper are: q-bio