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Near-optimal two-mode spin squeezing via feedback

Dominic W. Berry·Barry C. Sanders
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Abstract

We propose a feedback scheme for the production of two-mode spin squeezing. We determine a general expression for the optimal feedback, which is also applicable to the case of single-mode spin squeezing. The two-mode spin squeezed states obtained via this feedback are optimal for j=1/2 and are very close to optimal for j>1/2. In addition, the master equation suggests a Hamiltonian that would produce two-mode spin squeezing without feedback, and is analogous to the two-axis countertwisting Hamiltonian in the single mode case.

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Dominic W. Berry, Barry C. Sanders. 2002-09-20. Near-optimal two-mode spin squeezing via feedback. https://doi.org/10.1103/physreva.66.012313

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