- Quantum zigzag transition
- ion chains
- Efrat Shimshoni
- Giovanna Morigi
- Shmuel Fishman
- string of trapped ions
- zero temperature
- zigzag structure
- structural phase transition
- phase transition
- quantum optics
- quanten optik
- transverse trap potential
- short wavelength vibrational modes quantum critical point
- theoretical quantum physics
- universität des saarandes

https://arxiv.org/abs/1008.2326

Quantum zigzag transition in ion chains

(Submitted on 13 Aug 2010 (v1), last revised 16 Dec 2010 (this version, v2))

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.