Physics (Internal)

Heavy Fermion Superconductors: the little spin that could

This event is part of the Biophysics/Condensed Matter Seminar Series.

Abstract: Three years after the discovery of superfluid He-3 was discovered, Physicists observed heavy fermion superconductivity, yet the open mind-set required to embrace these results as a discovery, rather than a materials artifact was lacking. It took the efforts of a brave and determined set of heavy electron pioneers, to overcome this resistance and change the mind-set. Reflecting on this history leads us to the interesting question – how might we take a different path today in embracing the new challenges of correlated electron materials?

Today, we are increasingly conscious of the central role of spin as a driver for heavy electron metals and superconductors – not just as the glue of pairing – but as the basic fabric of these materials. Many of us suspect that the nexus of these phenomena lies at quantum critical points.

I’ll talk about how our ideas about spin and its role in the formation of the heavy electron state are changing and I will discuss the trials theorists face in seeking a proper mathematical description of the spin component of strongly correlated electron materials. As part of this presentation I will introduce you to two new “high temperature” heavy fermion superconductors, PuCoGa5 and NpPd2Al5 that appear to radically challenge the way we think about strongly correlated superconductivity.