Flux phase and its competition with superconductivity in the t-J model

Citation
E. Cappelluti et R. Zeyher, Flux phase and its competition with superconductivity in the t-J model, J SUPERCOND, 12(1), 1999, pp. 233-235
Citations number
5
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF SUPERCONDUCTIVITY
ISSN journal
08961107 → ACNP
Volume
12
Issue
1
Year of publication
1999
Pages
233 - 235
Database
ISI
SICI code
0896-1107(199902)12:1<233:FPAICW>2.0.ZU;2-L
Abstract
The phase diagram of the t-J model is investigated within the X-operator fo rmalism using the Baym-Kadanoff theory and a 1/N expansion. In this way, no auxiliary fields are introduced. For finite Coulomb repulsion, the system shows a strong competition between d-wave superconductivity and d-wave flux phase, leading to a strong suppression of superconductivity in the flux st ate. The underdoped region is characterized by flux order in the normal sta te, with a d-wave gap in the excitation spectrum, and by coexistence of bot h superconductivity and flux phases below the superconducting transition te mperature T-c. The balance between the two phases is determined by the shor t-range Coulomb repulsion, while the long-range part of Coulomb interaction prevents phase separation and leads to incommensurate charge-density-wave state far away from the superconducting region.