Odd-Frequency Superconductivity in Sr2RuO4 Measured by Kerr Rotation

We establish the existence of bulk odd-frequency superconductivity in Sr2RuO4 and show that an intrinsic Kerr effect is direct evidence of this state. We use both general two-and three-orbital models, as well as a realistic tight-binding description of Sr2RuO4 to demonstrate that odd-frequency pairing arises due to finite hybridization between different orbitals in the normal state, and is further enhanced by finite interorbital pairing.