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arXiv · 0807.3500

Spatial correlation functions for the collective degrees of freedom of many trapped ions

Nicolas C. Menicucci·G. J. Milburn
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Abstract

Spatial correlation functions provide a glimpse into the quantum correlations within a quantum system. Ions in a linear trap collectively form a nonuniform, discretized background on which a scalar field of phonons propagates. Trapped ions have the experimental advantage of each having their own "built-in" motional detector: electronic states that can be coupled, via an external laser, to the ion's vibrational motion. The post-interaction electronic state can be read out with high efficiency, giving a stochastic measurement record whose classical correlations reflect the quantum correlations of the ions' collective vibrational state. Here we calculate this general result, then we discuss the long detection-time limit and specialize to Gaussian states, and finally we compare the results for thermal versus squeezed states.

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Nicolas C. Menicucci, G. J. Milburn. 2008-07-22. Spatial correlation functions for the collective degrees of freedom of many trapped ions. https://arxiv.org/abs/0807.3500

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