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In this work we demonstrate that nonrandom mechanisms that lead to single-particle localization may also lead to many-body localization, even in the absence of disorder. In particular, we consider interacting spins and fermions in the presence of a linear potential. In the noninteracting limit, these models show the well-known Wannier–Stark localization. We analyze the fate of this localization in the presence of interactions. Remarkably, we find that beyond a critical value of the potential gradient these models exhibit nonergodic behavior as indicated by their spectral and dynamical properties. These models, therefore, constitute a class of generic nonrandom models that fail to thermalize. As such, they suggest new directions for experimentally exploring and understanding the phenomena of many-body localization. We supplement our work by showing that by using machine-learning techniques the level statistics of a system may be calculated without generating and diagonalizing the Hamiltonian, which allows a generation of large statistics. 

We show that a quantum many-body system may be controlled by means ofFloquet engineering, i.e., their properties may be controlled andmanipulated by employing periodic driving. We present a concrete drivingscheme that allows control over the nature of mobile units and theamount of diffusion in generic many-body systems. We demonstrate theseideas for the Fermi-Hubbard model, where the drive renders doublyoccupied sites (doublons) the mobile excitations in the system. Inparticular, we show that the amount of diffusion in the system and thelevel of fermion-pairing may be controlled and understood solely interms of the doublon dynamics. We find that under certain circumstancesthe diffusion in 1 1 Dsystems may be eliminated completely for extremely long times. Weconclude our work by generalizing these ideas to generic many-bodysystems.