SmallTalks "Topological light interacting with matter: a novel paradigm to explore quantum materials"

Abstract 

Control and manipulation of quantum materials is of paramount significance, both for fundamental characterization and for quantum technologies. Among others, light-matter interaction has recently gained traction because both optical counterpart of solid-state phenomena and emergent effects can be investigated. We extend this paradigm to a 3D topological optical quasiparticle called optical Hopfion - a knotted structure presenting robust topological protection, resolution on ultrafast time-scales, localization on nanometer-scale - as novel source to probe and to regulate properties and phases of matter. In this talk we present the magnetic response induced by optical hopfion-matter coupling. By relating the induced magnetization to the topological index associated to the hopfion, we identify the quantum inverse Faraday effect. This result paves the way for promising application in optical communication protocols, where information can be assigned to a topological index.