Rupin et al., App. Phys. Lett. (2015)

Based on the experimental configuration described in Figure 1, we exploit optimally the spatio-temporal degrees of freedom available inside the elastic metamaterial for flexural surface plate waves (composed of long aluminum rods closely packed on a sub-wavelength scale) to perform super-focusing (equivalent to super-resolution in imaging). We use the large sub-wavelength propagative bands caused by the strong hybridizations with the three first compresionnal resonances of the rods as revealed by the dispersion relation in Fig.2. Using an advanced single-emission based inversion technique, we manage to obtain a super-focusing of less than a sixth of a wavelength.