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arXiv · 1410.3388

Designing Frustrated Quantum Magnets with Laser-Dressed Rydberg Atoms

Alexander W. Glaetzle·Marcello Dalmonte·Rejish Nath·Christian Gross·Immanuel Bloch·Peter Zoller
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Abstract

We show how a broad class of lattice spin-1/2 models with angular- and distance-dependent couplings can be realized with cold alkali atoms stored in optical or magnetic trap arrays. The effective spin-1/2 is represented by a pair of atomic ground states, and spin-spin interactions are obtained by admixing van der Waals interactions between fine-structure split Rydberg states with laser light. The strengths of the diagonal spin interactions as well as the "flip-flop", and "flip-flip" and "flop-flop" interactions can be tuned by exploiting quantum interference, thus realizing different spin symmetries. The resulting energy scales of interactions compare well with typical temperatures and decoherence time-scales, making the exploration of exotic forms of quantum magnetism, including emergent gauge theories and compass models, accessible within state-of-the-art experiments.

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Alexander W. Glaetzle, Marcello Dalmonte, Rejish Nath, Christian Gross, Immanuel Bloch, Peter Zoller. 2015-04-30. Designing Frustrated Quantum Magnets with Laser-Dressed Rydberg Atoms. https://doi.org/10.1103/physrevlett.114.173002

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