Upper limit on spontaneous supercurrents in Sr${}_2$RuO${}_4$

J. R. Kirtley, C. Kallin, C. W. Hicks +5

It is widely believed that the perovskite Sr${}_2$RuO${}_4$ is an unconventional superconductor with broken time reversal symmetry. It has been predicted that superconductors with brok…