We show that, in a many‐body system, all particles can be strongly confined to the initially occupied sites for a time that scales as a high power of the ratio of the bandwidth of site energies to the hopping amplitude. Such time‐domain formulation is complementary to the formulation of the many‐body localization of all stationary states with a large localization length. The long localization lifetime is achieved by constructing a periodic sequence of site energies with a large period in a one‐dimensional chain. The scaling of the localization lifetime is independent of the number of particles for a broad range of the coupling strength. The analytical results are confirmed by numerical calculations.
How many particles make up a chaotic many-body quantum system?
We numerically investigate the minimum number of interacting particles,which is required for the onset of strong chaos in quantum systemson a one-dimensional lattice with short-range and long-range interactions.We consider multiple system sizes which are at least three times largerthan the number of particles and find that robust signatures of quantumchaos emerge for as few as 4 particles in the case of short-rangeinteractions and as few as 3 particles for long-range interactions,and without any apparent dependence on the size of the system.
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- Award ID(s):
- 1936006
- NSF-PAR ID:
- 10308884
- Date Published:
- Journal Name:
- SciPost Physics
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2542-4653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.21468/SciPostPhys.10.4.088
