Figure 3.

The eigenfunctions U₀ and U₁ shown for the comb-like structure with a=7 (cf. figure 2d). These are for the standing wave frequencies Ω₀ in table 1 with (a–d) for ascending Ω₀. In each panel, U₀ is shown on the left and U₁ on the right. (Online version in colour)