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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Probing the edge between integrability and quantum chaos in interacting few-atom systems
Interacting quantum systems in the chaotic domain are at the core of various ongoing studies of many-body physics, ranging from the scrambling of quantum information to the onset of thermalization. We propose a minimum model for chaos that can be experimentally realized with cold atoms trapped in one-dimensional multi-well potentials. We explore the emergence of chaos as the number of particles is increased, starting with as few as two, and as the number of wells is increased, ranging from a double well to a multi-well Kronig-Penney-like system. In this way, we illuminate the narrow boundary between integrability and chaos in a highly tunable few-body system. We show that the competition between the particle interactions and the periodic structure of the confining potential reveals subtle indications of quantum chaos for 3 particles, while for 4 particles stronger signatures are seen. The analysis is performed for bosonic particles and could also be extended to distinguishable fermions.
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- Award ID(s):
- 1936006
- PAR ID:
- 10308879
- Date Published:
- Journal Name:
- Quantum
- Volume:
- 5
- ISSN:
- 2521-327X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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