Alignment of chiral order parameter domains in Sr_{2} RuO_{4} by magnetic field cooling

Abstract

Superconductivity in Sr${}_2$RuO${}_4$ is unconventional, believed to be of $p_x\pm i{p}_y$ pairing symmetry. These two degenerate order parameters allow the formation of chiral domains separated by domain walls. In a Josephson junction formed on the edge of a single crystal of Sr${}_2$RuO${}_4$, the chiral domains can create a variation of the phase in the tunneling direction causing interference effects which suppress and modulate the critical current of the junction. Cooling the junction in a magnetic field lifts the degeneracy between the order parameter states and induces a preferential chirality, significantly modifying the phase interference. We present experimental results on Sr${}_2$RuO${}_4$/Cu/Pb Josephson junctions cooled in a magnetic field showing a dramatic enhancement of their critical current, giving direct evidence for the presence of chiral domains and their alignment in a magnetic field.

5 pages, 5 figures

Cited by in corpus (1)

• Chiral P-Wave Order in Sr_2RuO_4