Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Staggered-spin contribution to nuclear spin-lattice relaxation in
  two-leg antiferromagnetic spin-1/2 ladders   We study the nuclear spin-lattice relaxation rate $1/T_1$ in the two-leg
antiferromagnetic spin-1/2 Heisenberg ladder. More specifically, we consider
the contribution to $1/T_1$ from the processes with momentum transfer
$(\pi,\pi)$. In the limit of weak coupling between the two chains, this
contribution is of activation type with gap $2\Delta$ at low temperatures
($\Delta$ is the spin gap), but crosses over to a slowly-decaying temperature
dependence at the crossover temperature $T\approx\Delta$. This crossover
possibly explains the recent high-temperature NMR results on ladder-containing
cuprates by T. Imai et al.

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The categories of this paper are: math
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
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The categories of this paper are: cs
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
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The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat