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arXiv · 1406.5094

Hidden Frustrated Interactions and Quantum Annealing in Trapped Ion Spin-Phonon Chains

Pedro Nevado·Diego Porras
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Abstract

We show that a trapped ion chain interacting with an optical spin-dependent force shows strong frustration effects due to the interplay between long-range interactions and the dressing by optical phases. We consider a strong spin-phonon coupling regime and predict a quantum phase diagram with different competing magnetic and structural orders. In a highly frustrated region, the system shows enhanced quantum fluctuations and entanglement characteristic of spin-liquid phases. We propose and describe within a mean-field approach a quantum annealing process to induce a quasi-adiabatic evolution towards the ground state.

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Pedro Nevado, Diego Porras. 2015-12-10. Hidden Frustrated Interactions and Quantum Annealing in Trapped Ion Spin-Phonon Chains. https://doi.org/10.1103/physreva.93.013625

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