Orbital-singlet pairing and order parameter symmetry in Sr_2RuO_4
arXiv:cond-mat/0208301
Abstract
Based on the degeneracy of the d_{zx} and d_{yz} orbitals in Sr_2RuO_4 it is argued that the Cooper pairs condense in orbital singlets. Together with the spin-triplet wave functions the real-space wave function then is symmetric. Considering interaction effects the order parameter is found to have A_{1g} symmetry consistent with a number of experimental observations. The sensitivity of the material on non-magnetic impurities follows in a straightforward manner from the orbital-singlet configuration.
4 pages REVTEX, 3 figures