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arXiv · 1606.05582

Designing exotic many-body states of atomic spin and motion in photonic crystals

Marco T. Manzoni·Ludwig Mathey·Darrick E. Chang
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Abstract

Cold atoms coupled to photonic crystals constitute an exciting platform for exploring quantum many-body physics. Here we investigate the strong coupling between atomic internal ("spin") degrees of freedom and motion, which arises from spin-dependent forces associated with the exchange of guided photons. We show that this system can realize a remarkable and extreme limit of quantum spin-orbital systems, where both the direct spin exchange between neighboring sites and the kinetic energy of the orbital motion vanish. We find that this previously unexplored system has a rich phase diagram of emergent orders, including spatially dimerized spin-entangled pairs, a fluid of composite particles comprised of joint spin-phonon excitations, phonon-induced N\'eel ordering, and a fractional magnetization plateau associated with trimer formation.

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Marco T. Manzoni, Ludwig Mathey, Darrick E. Chang. 2016-06-17. Designing exotic many-body states of atomic spin and motion in photonic crystals. https://doi.org/10.1038/ncomms14696

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