Figure 5
From: Directional subradiance from helical-phase-imprinted multiphoton states
The far-field Ω f (θ, ϕ) of \(\hat{x}\)-polarized HPI two-photon states for N ϕ = 8 and Nr,z = 1, 2 and 3 in the stacked and concentric rings. For single ring, we plot two subradiant states (a) l = 2 and (b) l = 4 for comparisons. For stacked rings, the subradiant states with (c) l = 2 and (e) l = 4 are illustrated with N z = 2 and 3 from left to right. Similarly for concentric rings, the subradiant (left) and superradiant (right) states respectively with (d) l = 2 and (f) l = 4 are illustrated with N r = 2 and 3 from left to right. The viewing angle and other parameters are the same as in Fig. 2(a), and stacked ring separation d z /λ = 0.35, concentric inter-ring distance d r /λ = 0.2.
