Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unconventional temperature enhanced magnetism in iron telluride   Highly energetic magnetic fluctuations, discovered in high-temperature
superconductors (HTSC) by inelastic neutron scattering (INS), are now widely
believed to be vital for the superconductivity. In two competing scenarios,
they either originate from local atomic spins, or are a property of cooperative
spin-density-wave (SDW) behavior of conduction electrons. Both assume clear
partition into localized electrons, giving rise to local spins, and itinerant
ones, occupying well-defined, rigid conduction bands. Here, by performing an
INS study of spin dynamics in iron telluride, a parent material of one of the
iron-based HTSC families, we have discovered that this very assumption fails,
and that conduction and localized electrons are fundamentally entangled. We
find that the real-space structure of magnetic correlations can be explained by
a simple local-spin plaquette model. However, the effective spin implicated in
such a model, appears to increase with the increasing temperature. Thus, we
observe a remarkable redistribution of magnetism between the two groups of
electrons, which occurs in the temperature range relevant for the
superconductivity. The analysis of magnetic spectral weight shows that the
effective spin per Fe at T \approx 10 K, in the antiferromagnetic phase,
corresponds to S \approx 1, consistent with the recent analyses that emphasize
importance of Hund's intra-atomic exchange. However, it grows to S \approx 3/2
in the disordered phase, a result that profoundly challenges the picture of
rigid bands, broadly accepted for HTSC.

12
The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-fin