Theoretical seminar | 25 November 2020
Continuous media and metamaterials with a near-zero refractive index (NZI media) provide alternative pathways for the control and manipulation of light-matter interactions. The exotic behavior of NZI media is rooted in the fact that the wavelength gets effectively stretched as the refractive index vanishes. This allows for pathological solutions to the wave equation, including spatially static field distributions that nevertheless dynamically oscillate in time. This paradoxical behavior gives access to a regime of qualitatively different wave dynamics, where the importance of the geometry is lessened, and certain observables are invariant with respect to geometrical deformations, even including changes in the topology of the system.
In this talk, I’ll review and discuss some of the most relevant aspect of classical and quantum electrodynamics of NZI media including: (i) The behavior of NZI media as ideal electromagnetic fluids. (ii) The existence of geometry invariant resonant cavities. (iii) Violation of effective medium theory geometrical restrictions, enabling, for example, single unit-cell metamaterials. (iv) Quantum light emission in a vacuum depleted of optical modes. (v) Experimental demonstration of thermal emitters based on NZI media.