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Optimally squeezed spin states

A. G. Rojo
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Abstract

We consider optimally spin-squeezed states that maximize the sensitivity of the Ramsey spectroscopy, and for which the signal to noise ratio scales as the number of particles $N$. Using the variational principle we prove that these states are eigensolutions of the Hamiltonian $ H(λ)=λS_z^2-S_x, $ and that, for large $N$, the states become equivalent to the quadrature squeezed states of the harmonic oscillator. We present numerical results that illustrate the validity of the equivalence.

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A. G. Rojo. 2003-03-20. Optimally squeezed spin states. https://doi.org/10.1103/physreva.68.013807

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