Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconducting gap for a 2-leg t-J ladder   Single-particle diagonal and off-diagonal Green's functions of a 2-leg t-J
ladder at 1/8-doping are investigated by Exact Diagonalisations techniques. A
numerically tractable expression for the superconducting gap is proposed and
the frequency dependence of the real and imaginary parts of the gap are
determined. The role of the low-energy gapped spin modes whose energies are
computed by a (one-step) Contractor Renormalization procedure are discussed.

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The categories of this paper are: funct-an
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph