Speaker
Description
Quantum materials demand a nonperturbative reformulation of optics: matrix-valued band Hamiltonians and quantum geometry replace the parabolic bands and optical Bloch framework of conventional semiconductor optics. I will organize this emerging field around four paradigms: Floquet engineering, dressing Bloch bands by periodic drives; Schwinger production, generalizing Zener tunneling to Dirac and Mott systems; Berry geometry, underlying anomalous and shift-current responses and threading through the others as their geometric backbone; and Lorentz boosts, which exploit the emergent Lorentz invariance of Dirac quasiparticles to recast spacetime-modulated drives in a co-moving frame[1]. Propagating waves then act as dynamical backgrounds for emergent relativistic field theories: subluminal drives yield topological spacetime crystals, while superluminal drives enter a nonperturbative regime hosting Cherenkov-type emission—rendering quantum materials a laboratory for nonequilibrium relativistic phenomena[2].
Reference:[1] TO, arXiv:2407.21458 (2024), [2] TO, Swati Chaudhary, in progress.