This theory-led IRG co-designs materials platforms, including van der Waals heterostructures, misfit superlattices, and molecular crystals, together with engineered electromagnetic environments such as optical cavities, to stabilize quantum phases that have no equilibrium counterpart. Targets include cavity-modified superconductivity, light-engineered topological states, and hidden fractional states, reached without relying on intense laser pulses. The team is establishing quantitative design rules for creating and reconfiguring quantum matter far from equilibrium.