Nonequilibrium quasistationary spin disordered state in ?-RuCl3

We photoexcite high-energy holon-doublon pairs as a way to alter the magnetic free energy landscape and resulting phase diagram of the frustrated honeycomb magnet ??-RuCl3. The pair recombination through multimagnon emission is tracked through the time evolution of the magnetooptical response originating from ??-RuCl3???s competing zigzag spin-ordered ground state. A small holon-doublon density suffices to reach a spin-disordered state. The phase transition is described within a dynamical Ginzburg-Landau framework, corroborating the quasistationary nature of the transient phase. Our work suggests a new route to reach a nontrivial spin-disordered state in Kitaev-like magnets.