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arXiv · 1910.00023

Multiparticle interactions for ultracold atoms in optical tweezers: Cyclic ring-exchange terms

Abstract

Dominant multi-particle interactions can give rise to exotic physical phases with anyonic excitations and phase transitions without local order parameters. In spin systems with a global $SU(N)$ symmetry, cyclic ring-exchange couplings constitute the first higher-order interaction in this class. In this letter we propose a protocol how $SU(N)$ invariant multi-body interactions can be implemented in optical tweezer arrays. We utilize the flexibility to re-arrange the tweezer configuration on time scales short compared to the typical lifetimes, in combination with strong non-local Rydberg interactions. As a specific example we demonstrate how a chiral cyclic ring-exchange Hamiltonian can be implemented in a two-leg ladder geometry. We study its phase diagram using DMRG simulations and identify phases with dominant vector chirality, a ferromagnet, and an emergent spin-$1$ Haldane phase. We also discuss how the proposed protocol can be utilized to implement the strongly frustrated $J-Q$ model, a candidate for hosting a deconfined quantum critical point.

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Annabelle Bohrdt, Ahmed Omran, Eugene Demler, Snir Gazit, Fabian Grusdt. 2019-09-30. Multiparticle interactions for ultracold atoms in optical tweezers: Cyclic ring-exchange terms. https://doi.org/10.1103/physrevlett.124.073601

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