2022 SCIENCE & ENGINEERING GRANTS

Today's digital technology uses binary logic with only two states: on or off. Imagine how society would be transformed if we had devices with thousands of logical states that are coupled together! Dramatic improvements in power consumption and density of computing elements can be achieved by multinary technology utilizing topologically protected ensembles of electron spins. While coupling and control of topological spin ensembles are inaccessible to standard probes, such as conventional light, this team of researchers from Rutgers University and the New Jersey Institute of Technology propose a new paradigm: using topological vortex light with orbital angular momentum (OAM). They hypothesize that only a probe with the topology, energy, and length scale matching the topological quantum spin ensembles can couple effectively to those spin ensembles. Vortex beams meet these requirements, and the team's initial discoveries in the THz energy range support this hypothesis. The researcher's objectives include creating, reading, and manipulating previously inaccessible quantum spin states with vortex beams using a wide range of OAM (up to a thousand). Examples include topologically-protected chiral spin textures, vortices, skyrmions, hopfions, and quantum Hall states with multivalued topological indices. Specifically, they will attempt to: understand the mechanism of and optimize the coupling between THz, visible, and x-ray vortex beams and topological spin states; explore the dynamics of topological transitions in quantum spin states by vortex beams; and, attempt preliminary multinary device implementation of their scientific discoveries. This work is expected to have tremendous impact on its scientific field and society, opening new frontiers in quantum magnetism, enabling innovative multinary electronics, and influencing artificial intelligence.