Disorder Enhanced Thermalization in Interacting Many-Particle System

Recent advancements in theoretical and experimental research have intensified the study of nonequilibrium properties in correlated many-particle systems. A crucial aspect is understanding thermalization after interaction quenches, particularly in interacting fermionic systems. Building upon previous studies on the half-filled Hubbard model, which identified two distinct thermalization regimes, we investigate the impact of disorder on thermalization effects in interacting many-particle systems. We introduce an extension of the non-equilibrium dynamical mean field theory to incorporate the effects of static random disorder in the dynamics of a many-particle system by integrating out different disorder configurations by leveraging the normalization property of the Schwinger-Keldysh partition function. This approach circumvents the need for explicit disorder averaging over numerous realizations and thus offers computational advantages over traditional methods like the Coherent Potential Approximation. We use this method to study the non-equilibrium transient dynamics of the Fermi Anderson-Hubbard model following an interaction and disorder quench. We find that weak random disorder promotes thermalization. In the weak coupling regime, the jump in the quasiparticle weight in the prethermal regime is suppressed by random disorder while in the strong-coupling regime, random disorder reduces the amplitude of the quasiparticle weight oscillations. These results highlight the importance of disorder in the dynamics of many-particle systems.