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Calculation of Delta (k,omega) for a 2D t-J cluster

Didier Poilblanc·D. J. Scalapino
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Abstract

Using numerical techniques, the diagonal and off-diagonal superconducting one-electron Green's functions are calculated for a two-dimensional (2D) t-J model on a periodic 32-site cluster at low doping. From these Green's functions, the momentum and frequency dependence of the pairing gap $Δ({\bf k}, ω)$ are extracted. It has $d_{x^2-y^2}$ symmetry and exhibits $ω$-dependent structure which depend upon J/t. We find that the pairing gap persists down to small J/t values. The frequency- and momentum-dependent renormalized energy and renormalization factor are also calculated.

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Didier Poilblanc, D. J. Scalapino. 2002-02-27. Calculation of Delta (k,omega) for a 2D t-J cluster. https://doi.org/10.1103/physrevb.66.052513

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