Fig. 5: BIC robustness under defaults.
From: Observation of two-dimensional acoustic bound states in the continuum
Panel a shows the energy distribution for a ℓ = 2 mode with all the holes in the structrue (original cluster). The illustration showing the holes in the cluster, however, has one missing hole, indicating the position of the hole missing for panel b. Colour points (orange, green, blue and red) indicate the position of the measured points for the other panels. Panel b shows the spectra of the measured points, both for the original cluster (dotted lines) and for the missing hole scenario (full lines). Panel c shows the ratio between the spectrum coefficient at 5016 Hz (which corresponds to the mode) for the missing hole scenario and the original one. The angle in this graph indicates the position of the missing hole. Illustration d shows the picture of the plate for three different cases, in which we have been successively removing holes from the cluster. The third picture has five consecutive holes missing. Panel e shows the temporal envelope of the signal measured at the point x = 3.5 cm.
