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Two species of mutually interacting ultracold bosonic atoms are studied in a ring-shaped trap with a species-selective azimuthal lattice which may rotate. We examine the spectrum and the states in a collective spin formalism. The system can be modeled as a pair of coupled Lipkin-Meshkov-Glick Hamiltonians, and can be used to generate a high degree of entanglement. The Hamiltonian has two components: a linear part that can be controlled by manipulating the azimuthal lattice, and an interaction-dependent quadratic part. Exact solutions are found for the quadratic part for equal strengths of intraspecies and interspecies interactions. In different regimes the Hamiltonian can emulate a beam splitter or a two-mode squeezer of quantum optical systems. We study entanglement properties of the ground state of the Hamiltonian in dependence on various parameters with the prospect of possible quantum information and metrology applications.
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This content will become publicly available on May 13, 2026
Interspecies interactions in dual, fibrous gels enable control of gel structure and rheology
Natural and synthetic multicomponent gels display emergent properties, which implies that they are more than just the sum of their components. This warrants the investigation of the role played by interspecies interactions in shaping gel architecture and rheology. Here, using computer simulations, we investigate the effect of changing the strength of the interactions between two species forming a fibrous double network. Simply changing the strength of interspecies lateral association, we generate two types of gels: one in which the two components demix and another one in which the two species wrap around each other. We show that demixed gels have structure and rheology that are largely unaffected by the strength of attraction between the components. In contrast, architecture and material properties of intertwined gels strongly depend on interspecies “stickiness” and volume exclusion. These results can be used as the basis of a design principle for double networks which are made to emphasize either stability to perturbations or responsiveness to stimuli. Similar ideas could be used to interpret naturally occurring multicomponent gels.
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- Award ID(s):
- 2118912
- PAR ID:
- 10647220
- Publisher / Repository:
- NAS
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 122
- Issue:
- 19
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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