Even parity, orbital singlet, and spin triplet pairing for superconducting LaFeAsO1-xFx.
We examine the spin-triplet superconducting state of even parity mediated by ferromagnetic Hund's coupling between electrons in two almost degenerate orbital bands. This state may be realized in the recently discovered LaFeAsO(1-x)F(x). It is robust against orbital-independent disorder. The splitting of the orbital degeneracy suppresses superconductivity and leads to an anisotropic spectrum in the Bogoliubov quasiparticle. The former predicts a strong pressure dependence of T(c) and the latter predicts Fermi pockets, which may be tested in angle resolved photoemission spectra.
Dai
Xi
X
Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing, China. daix@aphy.iphy.ac.cn
Fang
Zhong
Z
Zhou
Yi
Y
Zhang
Fu-Chun
FC