A study of nearly-magnetic metals - Canceled

The contemporary understanding of the behavior of electrons in solids took the better part of a half century to develop - it turns out to be remarkably robust, only failing to describe the properties of certain exotic materials in extreme environments. In these circumstances we find states of matter that push the boundaries of our understanding of quantum many-body physics, and that can host states of potential applicative value such as high-temperature or topological superconductivity. In this talk I will discuss two such cases, both in metals which are "nearly-magnetic". In the first part of the talk, I explore the properties of a cerium based metal, where strong coulomb repulsion between f-level valence electrons tends to localize them to their host atoms. I will present evidence for a doping-induced delocalization transition of these electrons, and indirect evidence that such a transition causes the electrons to “fractionalize” into separate spin- and charge-carrying degrees of freedom. In the second part of the talk, I present data on a novel metallic system, which is found to host a superconducting phase in close proximity to ferromagnetism. I discuss our efforts to electrically control the magnetism and superconductivity in this material with an eye towards spintronics and quantum information processing applications.

Speakers: Nikola Maksomovic, UC Berkeley

Editor's Note: This lecture has been replaced with another, given by Emma Regan of UC Berkeley, at the same time and date.  See our listing for that lecture.  We leave this listing here for completeness.