Gorkov equations for a pseudogapped high-temperature superconductor - art.no. 144516

Citation
B. Giovannini et C. Berthod, Gorkov equations for a pseudogapped high-temperature superconductor - art.no. 144516, PHYS REV B, 6314(14), 2001, pp. 4516
Citations number
37
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
01631829 → ACNP
Volume
6314
Issue
14
Year of publication
2001
Database
ISI
SICI code
0163-1829(20010401)6314:14<4516:GEFAPH>2.0.ZU;2-C
Abstract
A phenomenological theory of superconductivity based on the two-body Cooper on propagator is presented. This theory takes the form of a modified Gorkov equation for the Green's function and allows one to model the effect of lo cal superconducting correlations and long-range phase fluctuations on the s pectral properties of high-temperature superconductors, both above and belo w T-c. A model is proposed for the Cooperon propagator, which provides a si mple physical picture of the pseudogap phenomenon, as well as insights into the doping dependence of the spectral properties. Numerical calculations o f the density of states and spectral functions based on this model are also presented, and compared with the experimental tunneling (STM) and photoemi ssion (ARPES) data. It is found, in particular, that the sharpness of the p eaks in the density of states is related to the strength and the range of t he superconducting correlations and that the apparent pseudogap in STM and ARPES can be different, although the underlying model is the same.