Atomic states with spectroscopic squeezing
G. S. Agarwal, Ravinder Rupchand Puri · Physical Review A · 1994
The spectroscopic squeezing characteristics of the angular-momentum state exp(\ensuremath{\theta}${\mathit{S}}_{\mathit{z}}$)exp[-(i\ensuremath{\pi}/2)${\mathit{S}}_{\mathit{y}}$]\ensuremath{\Vert}S,m〉 are calculated. The parameter \ensuremath{\surd}2S \ensuremath{\Delta}${\mathit{S}}_{\mathit{x}}$/\ensuremath{\Vert}〈${\mathit{S}}_{\mathit{z}}$〉\ensuremath{\Vert} is shown to be less than or equal to 1 and takes the asymptotic value (1+S${)}^{\mathrm{\ensuremath{-}}1/2}$ as \ensuremath{\theta}\ensuremath{\rightarrow}0 if m\ensuremath{\approxeq}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.