Probing the configuration and dynamics of order parameter domains in Sr$_{2}$RuO$_{4}$ by Josephson interferometry

We observe anomalous features in the magnetic field dependence of the critical current of Josephson junctions formed between conventional superconductors and the ruthenate superconductor Sr$_{2}$RuO$_{4}$, including magnetic hysteresis, switching noise, and a wide variation of qualitatively different diffraction pattern shapes.~ All of this behavior can be explained by assuming a complex p-wave order parameter of the form p$_{x}$+ip$_{y}$ that supports a dynamical structure of domains of different chirality and orientation.~ To test this hypothesis, we are studying the effects of magnetic field cooling on the junction critical current.~ We find a substantial enhancement of the critical current in field cooled samples, consistent with chiral domains that couple to an applied magnetic field.