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arXiv · 1008.2326

Quantum zigzag transition in ion chains

Efrat Shimshoni·Giovanna Morigi·Shmuel Fishman
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Abstract

A string of trapped ions at zero temperature exhibits a structural phase transition to a zigzag structure, tuned by reducing the transverse trap potential or the interparticle distance. The transition is driven by transverse, short wavelength vibrational modes. We argue that this is a quantum phase transition, which can be experimentally realized and probed. Indeed, by means of a mapping to the Ising model in a transverse field, we estimate the quantum critical point in terms of the system parameters, and find a finite, measurable deviation from the critical point predicted by the classical theory. A measurement procedure is suggested which can probe the effects of quantum fluctuations at criticality. These results can be extended to describe the transverse instability of ultracold polar molecules in a one dimensional optical lattice.

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Efrat Shimshoni, Giovanna Morigi, Shmuel Fishman. 2010-12-16. Quantum zigzag transition in ion chains. https://doi.org/10.1103/physrevlett.106.010401

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