Condensed Matter Seminar: Control of electrons and polaritons by patterning the 3D environment of a 2D material

An important, yet sometimes understated property of 2D materials is that they are embedded in a 3D environment, which makes them amenable to external manipulation in ways in which 3D materials are not. In this talk, I will discuss two applications of this concept: 

(1) Artificial superlattices in quantum materials, such as graphene. Using a newly developed technique, I will show that a superlattice potential can be electrostatically induced with superlattice periods approaching the moiré pattern in magic angle graphene. Specifically, I will discuss surprising magnetotransport results in Kagome superlattice and the prospects of this approach to produce artificial superconductors. 

(2) Confining hyperbolic phonon polaritons by modulated metallic screening. I will show that polaritons can be confined to volumes 8 orders of magnitude smaller than the volume of a vacuum photon (λ_0^3), while still maintaining an appreciable quality factor (Q~100). This breaks away from the nanophotonics paradigm that deep subwavelength cavities always exhibit low quality factors (high absorption) and paves the way to exciting cavity quantum electrodynamics experiments.