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

Yuki Yanagi; Youichi Yamakawa; Yoshiaki Ōno

doi:10.1103/physrevb.81.054518

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arXiv · 0912.2392

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

Yuki Yanagi·Youichi Yamakawa·Yoshiaki Ōno

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Abstract

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'.

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Yuki Yanagi, Youichi Yamakawa, Yoshiaki Ōno. 2010-02-24. 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. https://doi.org/10.1103/physrevb.81.054518

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