Physics below the diffraction limit: From plasmas to light

Abstract

Elementary interactions among elements such as electrons, phonons, and other quasiparticles in quantum materials give rise to the emergence of intriguing phases and offer enormous opportunities for the development of quantum technologies. However, investigating these interactions at the relevant length scale requires high-resolution methods beyond traditional far-field optical imaging and spectroscopy techniques, which are constrained by the diffraction limit of light. I will introduce a powerful modern nano-optical technique and give examples of high-resolution probing of nanoscale physical phenomena and interactions in two classes of quantum materials: correlated oxides and van der Waals (vdW) crystals.