Interaction quenches in the two-dimensional fermionic Hubbard model

TL;DR

This paper investigates the non-equilibrium dynamics of the 2D fermionic Hubbard model after interaction quenches, revealing collective phenomena, distinct behaviors based on quench strength, and insights into relaxation processes.

Contribution

It provides the first detailed analysis of interaction quenches in the 2D fermionic Hubbard model, highlighting collective effects and relaxation mechanisms without prethermalization evidence.

Findings

Collapse-and-revival phenomena for strong quenches

Weak quenches show minimal oscillations

Relaxation rates vary with interaction strength

Abstract

The generic non-equilibrium evolution of a strongly interacting fermionic system is studied. For strong quenches, a collective collapse-and-revival phenomenon is found extending over the whole Brillouin zone. A qualitatively distinct behavior occurs for weak quenches where only weak wiggling occurs. Surprisingly, no evidence for prethermalization is found in the weak coupling regime. In both regimes, indications for relaxation beyond oscillatory or power law behavior are found and used to estimate relaxation rates without resorting to a probabilistic ansatz. The relaxation appears to be fastest for intermediate values of the quenched interaction.