Weak-coupling calculation of the gap structure of doped n-leg Hubbard ladders

N. Bulut; D. J. Scalapino

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Weak-coupling calculation of the gap structure of doped n-leg Hubbard ladders

N. Bulut·D. J. Scalapino

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Abstract

In weak coupling, the spin gap in doped, even, n-leg periodic Hubbard ladders reflects the energy to break a pair into separate quasiparticles. Here we investigate the structure of the gap within a spin-fluctuation exchange approximation. We also calculate the amplitude for removing a singlet pair from two lattice sites separated by a distance (l_x,l_y), which describes the internal structure of a pair.

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N. Bulut, D. J. Scalapino. 1996-09-16. Weak-coupling calculation of the gap structure of doped n-leg Hubbard ladders. https://arxiv.org/abs/cond-mat/9609136

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