Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Low-energy electronic structure in Y1-xCaxBa2Cu3O7-y comparison of t
  ime-resolved optical spectroscopy, NMR, neutron and tunneling data   Time-resolved optical measurements give information on the quasiparticle
relaxation dynamics in YBCO, from which the evolution of the gap with doping
and temperature can be systematically deduced. In this paper these optical
charge-channel `pseudogap' data are compared with the `pseudogap' obtained from
the NMR Knight shift Ks, spin polarized neutron scattering (SPNS) and single
particle tunneling measurements. A simple energy level diagram is proposed to
explain the different `gap' magnitudes observed by different spectroscopies in
Y1-xCaxBa2Cu3O7-y, whereby the spin gap Delta_s in NMR and SPNS corresponds to
a triplet local pair state, while Delta_p in the charge excitation spectrum
corresponds to the pair dissociation energy. At optimum doping and in the
overdoped state, an additional T-dependent gap becomes evident, which closes at
T_c, suggesting a cross-over to a more conventional BCS-like superconductivity
scenario.

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The categories of this paper are: hep-lat
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
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The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph