SPICE Workshop on Non-equilibrium Quantum Materials Design, June 27th - 29th 2023
Martin Claassen
Irradiation with light provides a powerful tool to interrogate, control or induce quantum states in solids, however a microscopic understanding of light-matter coupling in interacting electron systems remains a profound challenge. In this talk, I will discuss how quantum geometry can grant a new handle and design principle to steer and probe strongly-correlated quantum materials using light, whereby photons must dynamically dress and deform the effective Wannier orbitals that comprise the material's interacting bands. This effect is generic to all interacting electron systems, however can dominate optical properties in materials with non-trivial quantum geometry or topology, leading to poorly-localized or obstructed Wannier functions. I will discuss ramifications for spectroscopic responses in flat-band materials and THz driving of moiré heterostructures such as twisted bilayer graphene, and argue that ultrafast pump-probe experiments can provide a new avenue to explore the rich phase diagram of these materials out of equilibrium.