Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Majoranas in mixed-valence insulators   A physical model for a mixed-valence impurity in a metal must satisfy the
Friedel screening theorem for both valences. Such a model is shown, following
earlier work which showed low energy singularities in it, to be supersymmetric,
leading to a free Majorana and a phase-shifted Majorana excitation. The theory
extended approximately to a lattice of mixed-valence ions at appropriate
filling gives, without fine-tuning the parameters, a protected gapless Majorana
fermion band across the chemical potential, besides the mixed-valence particle
and hole bands separated by gaps. In this situation the system is electrically
neutral in linear response but has de Haas-van Alphen oscillations. This is
used to explain the recently observed magneto-oscillations in mixed-valence
insulators as well as their accompanying low energy thermodynamic and
relaxation rate anomalies. Some predictions to test the validity of the
theoretical results are provided, the most striking of which is that there
should be extensive ground state entropy in such compounds.

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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: physics
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: econ