arXiv:cond-mat/0303053 · Physical review. B, Condensed matter
Superconducting fluctuations in the Luther-Emery liquid
E. Orignac, Didier Poilblanc
Abstract
The single-particle superconducting Green's functions of a Luther-Emery liquid is computed by bosonization techniques. Using a formulation introduced by Poilblanc and Scalapino [Phys. Rev. B 66, 052513 (2002)], an asymptotic expression of the superconducting gap is deduced in the long wavelength and small frequency limit. Due to superconducting phase fluctuations, the gap exhibits as a function of size L a ${(1/L)}^{{1/2K}_{\ensuremath{\rho}}}$ power-law decay as well as an interesting singularity at the spectral gap energy. Similarities and differences with the two-leg $t\ensuremath{-}J$ ladder are outlined.