Screening the Coulomb interaction leads to a prethermal regime in two-dimensional bad conductors

Abstract

The absence of thermalization in certain isolated many-body systems is of great fundamental interest. However, it is not well understood how the interplay of disorder and interactions affects thermalization, especially in two dimensions (2D), and experiments on solid-state materials remain scarce. We investigate nonequilibrium dynamics exhibited after a rapid change of electron density n s , in two sets of disordered 2D electron systems in Si, poorly coupled to a thermal bath. In the low conductivity regime at low n s , we find that, while the dynamics is glassy in devices with the long-range Coulomb interaction, in the case of screened Coulomb interaction the thermalization is anomalously slow, consistent with the proximity to a many-body-localized (MBL) phase, i.e. the MBL-like, prethermal regime. Our results demonstrate that the MBL phase