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Title: From Bloch oscillations to many-body localization in clean interacting systems
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.  more » « less
Award ID(s):
1733907
PAR ID:
10124896
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
ISSN:
0027-8424
Page Range / eLocation ID:
201819316
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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