Spin squeezing in a generalized one-axis twisting model
نویسندگان
چکیده
We investigate the dependence of spin squeezing on the polar angle of the initial coherent spin state |θ0, φ0〉 in a generalized one-axis twisting model, where the detuning δ is taken into account. We show explicitly that regardless of δ and φ0, previous results of the ideal one-axis twisting is recovered as long as θ0 = π/2. For a small departure of θ0 from π/2, however, the achievable variance (V−)min ∼ N, larger than the ideal case N. We also find that the maximal-squeezing time tmin scales as N. Analytic expressions of (V − )min and tmin are presented, which agree with numerical simulations. PACS numbers: 42.50.Lc,03.75.Nt, 05.30.Jp Spin squeezing in a generalized one-axis twisting model 2
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