Pseudo gap and superconducting gap in the d-p model

Citation
A. Kobayashi et al., Pseudo gap and superconducting gap in the d-p model, J PHYS CH S, 62(1-2), 2001, pp. 199-202
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
ISSN journal
0022-3697 → ACNP
Volume
62
Issue
1-2
Year of publication
2001
Pages
199 - 202
Database
ISI
SICI code
0022-3697(200101/02)62:1-2<199:PGASGI>2.0.ZU;2-Y
Abstract
We investigate pseudo gap and superconducting gap by using the extended sel f-consistent t-matrix approximation (ESTA) in the d-p model. We take the pa iring interaction mediated by the spin fluctuation and calculate the single -particle spectrum, the density of states and the superconducting gap Delta (sc)(k). The superconducting fluctuation induces excitaion gap Delta (fl)( k)(k) and large damping of quasi-particles, Gamma (k,omega), with d(x2-y2) symmetry. The effective gap Delta (k), which consists of Delta (fl)(k) and Delta (sc)(k), smoothly increases across the superconducting transition tem perature T-c as T decreases. As the hole-doping rate delta decreases, d(k) increases monotonously, while T,has a maximum at delta congruent to 0.11 an d decreases in the underdoped region. The damping near the Fermi energy rea ches a maximum at T,followed by sharp drop as T decreases. The pseudo gap i n the density of states is induced by not only Delta (k) but the omega -dep endence of T(k,omega). (C) 2000 Elsevier Science Ltd. All rights reserved.