Symmetry properties of the superconducting order parameter in Sr₂RuO₄

Symmetry properties of the superconducting order parameter (OP) in Sr₂RuO₄ have subjected to controversy in past several years. In this presentation we will discuss the symmetry properties of both the orbital and spin parts of the OP, showing that the odd-parity, spin-triplet pairing picture can account for all relevant data published thus far if a “spin-lattice locking” picture inspired by experimental observations in which electron spins are “locked” in a crystalline plane or axis by spin-orbital interaction is taken into account. We will also present new and unpublished data from phase-sensitive experiments based on Josephson effect. These results provide additional support to the odd-parity-pairing picture in Sr₂RuO₄.