Phenomenology of the superconducting state in Sr2RuO4

TL;DR

This paper investigates the superconducting state of Sr2RuO4, identifying its symmetry as an odd-parity pairing state and exploring the mechanisms stabilizing this state through spin fluctuations and spin-orbit coupling.

Contribution

It provides a theoretical analysis of the superconducting symmetry in Sr2RuO4 and proposes mechanisms for its stabilization based on spin fluctuations and spin-orbit interactions.

Findings

Superconducting state is identified as odd-parity d(k)=z(k_x ± i k_y).

Orbital dependent superconductivity supports a single-band model.

Spin fluctuation feedback and spin-orbit coupling stabilize the state.

Abstract

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.