Algorithm for obtaining the gradient expansion of the local density of states and the free energy of a superconductor
Lorenz Bartosch, Peter Kopietz
DOI 10.1103/PhysRevB.60.7452 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
We present an efficient algorithm for obtaining the gauge-invariant gradient expansion of the local density of states and the free energy of a clean superconductor. Our method is based on a new mapping of the semiclassical linearized Gorkov equations onto a pseudo-Schrödinger equation for a three-component wave function ψ→(x), where one component is directly related to the local density of states. Because ψ→(x) satisfies a linear equation of motion, successive terms in the gradient expansion can be obtained by simple linear iteration. Our method works equally well for real and complex order parameter, and in the presence of arbitrary external fields. We confirm a recent calculation of the fourth order correction to the free energy by Kosztin, Kos, Stone, and Leggett [Phys. Rev. B 58, 9365 (1998)], who obtained a discrepancy with an earlier result by Tewordt [Z. Phys. 180, 385 (1964)]. We also give the fourth order correction to the local density of states, which has not been published before.
Similar papers
Algorithm for obtaining the gradient expansion of the local density of states and the free energy of a superconductor
similarity 0.90Lorenz Bartosch & Peter Kopietz · 1999 · arXiv:cond-mat/9902042
Source status unknown — claims are unverified
Gradient expansion for the free energy of a clean superconductor
similarity 0.89Šimon Kos & Michael Stone
Source status unknown — claims are unverified
The Gradient Expansion for the Free-Energy of a Clean Superconductor
similarity 0.88Simon Kos & Michael Stone · 1998 · arXiv:cond-mat/9809182
Source status unknown — claims are unverified