Figure 4
Coincidence rate RCP(τ1, τ2) of the CP state according to Eq. (35) for θ = π/2. Panel (a): contour plot of RCP(τ1, τ2); Panels (b–d): plots of function RCP(τ1, τ1), RCP(τ1, 0) and RCP(0, τ2). In all the figures the delays times have been rescaled by the inverse of the width ΔΩ− of the bi-photon spectrum, and the rates have been rescaled by the plateau value. Notice that differently from the BP case reported in Fig. 3, this function never reaches zero: in particular at the origin of the coordinate axis it reaches the value 1 (this result being independent from the value of θ). The mean frequency ω0 was set equal to 5ΔΩ− and ΔΩ+ = ΔΩ−/5 so that Δω ≃ ΔΩ−/2 – see Eq. (15).
