Event Date Details:
Refreshments served at 3:30pm.
- Broida 1640
- Physics Department Colloquium
This talk starts by reviewing the remarkable theoretical and experimental progress in topological materials over the past decade. Three-dimensional topological insulators realize a particular electromagnetic coupling known as “axion electrodynamics”, and understanding this leads to an improved understanding of magnetoelectricity in all materials. We then turn to how topological Weyl and Dirac semimetals can show unique electromagnetic responses; we argue that in linear response the main observable effect solves an old problem via the orbital moment of Bloch electrons, and how in nonlinear optics there should be a novel approximately quantized photocurrent effect.