CMT Seminar - Light-matter interactions with photonic quasiparticles

Abstract: The interactions of matter with electromagnetic fields underlie very many physical phenomena. The physics of these interactions is greatly simplified by their weakness, enabling us to understand them largely at the lowest order in various parameters (e.g., field strength, atomic size, fine-structure constant). This understanding is challenged by recent experiments coupling light to collective electromagnetic excitations in solids ("photonic quasiparticles"), whose strongly confined electromagnetic fields can interact strongly with matter. In this talk, I will describe how the rules of light-matter interactions are altered when bound and free electrons interact with photonic quasiparticles. In the first part, I will discuss effects arising from the linear optical properties of these excitations, which give rise to new schemes for generating entangled photons, for X-ray sources, and even for high-energy particle detectors. In the second part, I will discuss the new physics arising from the nonlinear optical properties of these photonic quasiparticles. I will use these nonlinearities to construct a class of effectively high-order optical nonlinearities not realizable with natural optical materials. As an application, I show how this high-order nonlinearity enables the deterministic, steady-state generation of large optical Fock states.