A personal perspective on the unconventional superconductivity of Sr2RuO4

Abstract

I give a personal account of the unfolding story of the unconventional superconductivity of Sr2RuO4. This is a subject of topical importance in light of recent measurements that suggest that its order parameter may be even parity, contrary to the picture that had built up over the course of over two decades of research. With an eye on the past, I stress the generous encouragement that I received from Ted Geballe in the early years of my Sr2RuO4 research. Looking to the future, I give my opinion about why the Sr2RuO4 problem is of major significance to the development of the field of unconventional superconductivity, whatever order parameter symmetry is finally established to be the correct one.