Nonequilibrium Materials Design of Frustrated Mott Insulators*

Spurred by recent progress in melting, enhancement and induction of electronic order out of equilibrium, a promising prospect concerns accessing transient steady states of periodically-driven quantum systems, to affect electronic properties. In this talk, I will discuss how light can provide a handle to dynamically break symmetries in a class of frustrated Mott insulators with competing orders and tune the underlying magnetic interactions. In a Mott antiferromagnet, optical pumping below the charge gap can drive the system into Floquet steady states of a transient effective spin Hamiltonian, whereas heating remains suppressed for sufficiently short pulse widths. On the Kagome lattice, circularly-polarized light dynamically breaks parity and time-reversal symmetry and transiently induces a staggered scalar spin chirality contribution to the effective spin dynamics, revealing a stable photo-induced chiral spin liquid - the elusive ν=1/2 fractional quantum Hall effect of spins - in proximity to the equilibrium state. I will then discuss how transient manipulation of Mott insulators could serve as a tool to investigate dynamics of frustrated spin systems in pump-probe experiments.