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arXiv · 1405.6071

Quantum simulation of superexchange magnetism in linear ion crystals

Peter A. Ivanov·Naoum I. Karchev·Nikolay V. Vitanov·Dimitris G. Angelakis
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Abstract

We present a system for the simulation of Heisenberg models with spins $s=\frac{1}{2}$ and $s=1$ with a linear crystal of trapped ions. We show that the laser-ion interaction induces a Jaynes-Cummings-Hubbard interaction between the atomic V-type level structure and the two phonon species. In the strong-coupling regime the collective atom and phonon excitations become localized at each lattice site and form an effective spin system with varying length. We show that the quantum-mechanical superexchange interaction caused by the second-order phonon hopping processes creates a Heisenberg-type coupling between the individual spins. Trapped ions allow to control the superexchange interactions by adjusting the trapping frequencies, the laser intensity, and the detuning.

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Peter A. Ivanov, Naoum I. Karchev, Nikolay V. Vitanov, Dimitris G. Angelakis. 2015-02-10. Quantum simulation of superexchange magnetism in linear ion crystals. https://doi.org/10.1103/physreva.90.012325

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