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Superconducting gap for a 2-leg t-J ladder

Didier Poilblanc·D. J. Scalapino·Sylvain Capponi
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Abstract

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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Didier Poilblanc, D. J. Scalapino, Sylvain Capponi. 2003-03-28. Superconducting gap for a 2-leg t-J ladder. https://doi.org/10.1103/physrevlett.91.137203

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