Atomic states with spectroscopic squeezing

Abstract

The spectroscopic squeezing characteristics of the angular-momentum state exp(θ${\mathit{S}}_{\mathit{z}}$)exp[-(iπ/2)${\mathit{S}}_{\mathit{y}}$]‖S,m〉 are calculated. The parameter √2S Δ${\mathit{S}}_{\mathit{x}}$/‖〈${\mathit{S}}_{\mathit{z}}$〉‖ is shown to be less than or equal to 1 and takes the asymptotic value (1+S${)}^{\mathrm{-}1/2}$ as θ→0 if m≊0. This small value makes those states especially useful in applications where quantum noise reduction is required. Also, the spin-spin correlations of those states are nonzero and negative.