Figure 8
Plot of Hϕ as a function of the phase ϕ for three values of a = b = α: from bottom to top, α = 0.5, 0.8, 1.0 (black lines).
Left: horizontal blue dashed lines correspond to the values 4|α|2 of the QFI obtained for a single coherent state |α〉 as the probe state. Right: red dashed lines describe the behavior of Hϕ in the presence of uniform noise with γ = π/4.
