Two types of s-wave pairing due to magnetic and orbital fluctuations in the two-dimensional 16-band d-p model for iron-based superconductors
Source: Phys. Rev. B 81, 054518 (2010); doi:10.1103/PhysRevB.81.054518
Published 23 February 2010
We study superconductivity in the two-dimensional 16-band d-p model extracted from a tight-binding fit to the band structure of LaFeAsO, using the random phase approximation. When the intraorbital repulsion U is larger than the interorbital one U
, an extended s-wave (s±-wave) pairing with sign reversal of order parameter is mediated by antiferromagnetic spin fluctuations, while when U<U
another kind of s-wave (s++-wave) pairing without sign reversal is mediated by ferro-orbital fluctuations. The s++-wave pairing is enhanced due to the electron-phonon coupling and then can be expanded over the realistic parameter region with U>U
.
©2010 The American Physical Society
, an extended s-wave (s±-wave) pairing with sign reversal of order parameter is mediated by antiferromagnetic spin fluctuations, while when U<U
another kind of s-wave (s++-wave) pairing without sign reversal is mediated by ferro-orbital fluctuations. The s++-wave pairing is enhanced due to the electron-phonon coupling and then can be expanded over the realistic parameter region with U>U
.
©2010 The American Physical Society
| History: | Received 11 December 2009; revised 29 January 2010; published 23 February 2010 |
| Permalink: |
http://link.aps.org/abstract/PRB/v81/e054518 |
ADVERTISEMENT



no