Fig. 4: Zoomed-in view of the BIC and sharp resonances.
From: Phonon transmission through a nonlocal metamaterial slab
a Zoomed-in view of the bound-states-in-the-continuum (BIC) point highlighted by the yellow box in Fig. 3a. b Cuts through the data in panel a at three selected ratios \({K}_{3}/{K}_{1}\) (see dashed vertical lines in a). Extremely sharp resonance versus frequency \(\omega\) occur for parameters close to the BIC point (yellow and purple curves). At the BIC point (red curve), the sharp resonance disappears as incident waves strictly do not couple to the BIC.
