Orbital-singlet pairing and order parameter symmetry in Sr_2RuO_4

Ralph Werner

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Orbital-singlet pairing and order parameter symmetry in Sr_2RuO_4

Ralph Werner

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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.

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Ralph Werner. 2002-08-15. Orbital-singlet pairing and order parameter symmetry in Sr_2RuO_4. https://arxiv.org/abs/cond-mat/0208301

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