Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Significant enhancement of upper critical fields by doping and strain in
  Fe-based superconductors   We report measurements of Hc2(T) up to 85 Tesla on Ba1-xKxAs2Fe2 single
crystals and FeSe1-xTex films tuned by doping and strain. We observed an Hc2
enhancement by nearly 25 T at 30 K for the optimally-doped Ba1-xKxAs2Fe2 as
compared to the previous results and extraordinarily high slopes dHc2/dT =
250-500 T/K near Tc in FeSe1-xTex indicating an almost complete suppression of
the orbital pair-breaking. Theoretical analysis of Hc2(T) in FeSe1-xTex and the
optimally doped Ba1-xKxAs2Fe2 predicts an inhomogeneous
Fulde-Ferrel-Larkin-Ovchinnikov state for H//ab and T < 3-10 K, and shows that
Hc2 in multiband Fe based superconductor can be enhanced by doping and strain
much more effectively than by the conventional way of increasing disorder.

23
The categories of this paper are: solv-int
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: eess
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
1
The categories of this paper are: cs
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The categories of this paper are: cmp-lg