Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum critical scaling in the disordered itinerant ferromagnet
  UCo$_{1-x}$Fe$_x$Ge   Belitz-Kirkpatrick-Vojta (BKV) theory shows in excellent agreement with
experiment that ferromagnetic quantum phase transitions (QPTs) in clean metals
are generally first-order due to the coupling of the magnetization to
electronic soft modes, in contrast to the classical analogue that is an
archetypical second-order phase transition. For disordered metals BKV theory
predicts that the second order nature of the QPT is restored because the
electronic soft modes change their nature from ballistic to diffusive. Our
low-temperature magnetization study identifies the ferromagnetic QPT in the
disordered metal UCo$_{1-x}$Fe$_x$Ge as the first clear example that exhibits
the associated critical exponents predicted by BKV theory.

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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: funct-an
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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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: nucl-ex