# Condensed Matter Seminar: "Topological protection of photons"

Wed, 01/10/2018 - 16:00 - 17:00

Mikael Rechtsman (Penn State University)

Topological insulators are solid-state materials whose
transport properties are immune to defects and disorder due to underlying topological order. Perhaps the first such
phenomenon was the quantum Hall effect, wherein the Hall conductivity is
quantized and hence extremely robust. In this talk, I will present the
experimental observation of the topological protection of the transport of *photons* (rather than electrons
in the solid state) in complex dielectric structures. I will then present
the observation of optical Weyl points in the context of three-dimensional photonic crystals.
Applications of topological photonic devices include robust photonic
networks and delay lines, and potentially high-power single-mode lasing.

David Rittenhouse Laboratory, A4