Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reversible magnetization and critical fluctuations in systematically
  doped YBa$_2$Cu$_3$O$_{7-\delta}$ single crystals   The temperature and field dependence of reversible magnetization have been
measured on a YBa$_2$Cu$_3$O$_{7-\delta}$ single crystal at six different
doping concentrations. It is found that the data above 2 T can be described by
the scaling law based on the GL-LLL (lowest Landau level approach based on
Ginzburg-Landau theory) critical fluctuation theory yielding the values of the
slope of upper critical field $-\mathrm{d}H_{\mathrm{c2}}(T)/\mathrm{d}T$ near
$T_\mathrm{c}$. This set of values is self-consistent with that obtained in
doing the universal scaling for the six samples. Based on a simple
Ginzburg-Landau approach, we determined the doping dependence of the coherence
length $\xi$ which behaves in a similar way as that determined from $\xi= \hbar
v_\mathrm{F}/E_\mathrm{sc}$ with $E_\mathrm{sc}$ the superconducting energy
scale. Our results may suggest a growing coherence length towards more
underdoping.

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The categories of this paper are: q-alg
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int