Theory of Light-matter interactions
"Quantum Optics!"
Collective Phenomena in Engineered Quantum Systems/Quantum Many Body Physics with Photons
"Quantum optics but bigger and more complicated."
Complex Photonic Systems and Lasers
"Optics but bigger and less quantum."
Computational Modeling (QED/Lasers)
"How to get computers to do our research for us."
Physics of Computing and Computing with Physical Systems
"How to use our research to make computers, which can then do our research for us."