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arXiv · 0808.1957

Relationship between spin squeezing and single-particle coherence in two-component Bose-Einstein condensates with Josephson coupling

G. R. Jin·C. K. Law
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Abstract

We investigate spin squeezing of a two-mode boson system with a Josephson coupling. An exact relation between the squeezing and the single-particle coherence at the maximal-squeezing time is discovered, which provides a more direct way to measure the squeezing by readout the coherence in atomic interference experiments. We prove explicitly that the strongest squeezing is along the $J_z$ axis, indicating the appearance of atom number-squeezed state. Power laws of the strongest squeezing and the optimal coupling with particle number $N$ are obtained based upon a wide range of numerical simulations.

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G. R. Jin, C. K. Law. 2009-01-08. Relationship between spin squeezing and single-particle coherence in two-component Bose-Einstein condensates with Josephson coupling. https://doi.org/10.1103/physreva.78.063620

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