Relaxation Dynamics of Current-Induced Insulator-to-Metal Transition in Ca₂RuO₄

The Mott insulator Ca₂RuO₄ has garnered attention due to its rich electronic properties. Ca₂RuO₄ exhibits a first-order insulator-to-metal transition at Tc ~ 357K. This is accompanied by a structural transition and an increase in the c-axis parameter of the unit cell. Recent studies show that the current-induced insulator-to-metal transition reveals the formation of phase fronts between the metallic and insulating phases. The phase fronts exhibit stripe pattern along the crystal axes and the system goes through metastable states before stabilizing. To understand the nature of the coupling between the structural and electronic transitions, we applied an electric current pulse and drove the system into the metallic phase. As the system relaxes back into the insulating phase, there is residual dynamics in which the resistivity increases on long-time scales. A combined transport and x-ray photon correlation spectroscopy (XPCS) studies were performed on the structural Bragg peak revealing a current-driven slow dynamics in bulk single crystals of Ca₂RuO₄ and 2% Mn-doped Ca₂RuO₄.