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Entanglement and spin squeezing properties for three bosons in two modes

B. Zeng·D. L. Zhou·Z. Xu·L. You
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Abstract

We discuss the canonical form for a pure state of three identical bosons in two modes, and classify its entanglement correlation into two types, the analogous GHZ and the W types as well known in a system of three distinguishable qubits. We have performed a detailed study of two important entanglement measures for such a system, the concurrence $\mathcal{C}$ and the triple entanglement measure $τ$. We have also calculated explicitly the spin squeezing parameter $ξ$ and the result shows that the W state is the most ``anti-squeezing'' state, for which the spin squeezing parameter cannot be regarded as an entanglement measure.

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B. Zeng, D. L. Zhou, Z. Xu, L. You. 2005-01-18. Entanglement and spin squeezing properties for three bosons in two modes. https://doi.org/10.1103/physreva.71.042317

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