Opportunities Created by Spin-Orbit Interactions

Presented online via Bluejeans Meetings and in-person in the Marcus Nanotechnology Building, room 1116 on April 4, 2022 at 3:00 p.m..Gang Cao is a Professor of Physics at the University of Colorado Boulder. His research is driven by two interconnected thrusts — Discovery of New Quantum Materials and Control of Novel Quantum States. It encompasses a methodical search for new quantum materials, especially new 4d- and 5d-electron based materials, and a systematic effort to elucidate and control novel quantum states in these materials.Runtime: 64:29 minutesEffects of spin-orbit interactions in condensed matter are an important and rapidly evolving topic. A sea change occurred with the discovery of spin-orbit interactions in graphene by Mele and Kane, which has led to the exciting new field of physics addressing a rare interplay between spin-orbit and Coulomb interactions in condensed matter. I will describe an entirely new hierarchy of energy scales inherent in 4d- and 5d-electron based oxides and its unique consequences, highlighting discrepancies between experimental confirmation and theoretical proposals that address superconducting, topological and quantum spin liquid phases in iridates. I will then present our recent discoveries of novel quantum phenomena in iridates and ruthenates and conclude by venturing a perspective for research on spin-orbit-coupled oxides [1,2]. References: 1. Physics of Spin-Orbit-Coupled Oxides, Gang Cao and Lance E. De Long, Oxford University Press; Oxford, 2021 2. The Challenge of Spin-Orbit-Tuned Ground States in Iridates: A Key Issues Review, Gang Cao and Pedro Schlottmann, Reports on Progress in Physics, 81 042502 (2018