Figure 2
From: An analog of photon-assisted tunneling in a periodically modulated waveguide array

PAT in three-guide optical system.
(a) the minimum value of intensity of light at the initially populated guide-1, Min(P1) versus Ω2, with A = 6.6, ω = 3, Ω1 = 1; (b) the corresponding quasi-energy ε versus Ω2 with no level degeneracy and (c) the time-averaged population 〈Fj〉 belonging to the zero-energy (dark) Floquet state versus Ω2.