Phenomenology of the superconducting state in Sr2RuO4

The symmetry of the superconducting phase of Sr2RuO4 is identified as the odd-parity pairing state d(k)=\hat{z}(k_x \pm i k_y) based on recent experiments. The experimental evidence for the so-called orbital dependent superconductivity leads to a single-band description of superconductivity based on spin fluctuation mechanism. It is shown that the state \hat{z}(k_x \pm i k_y) can be stabilized by the spin fluctuation feedback mechanism analogous to the A-phase in 3He and by spin-orbit coupling effects.