We experimentally achieve selective wave filtering and polarization control in a three-
dimensional elastic frame embedding local resonators. By connecting multi-resonating
elements to a frame structure, a complete low-frequency, subwavelength bandgap with
strong selective filtering properties is obtained. Theory and experiments demonstrate the
metaframe capability to selectively stop transverse waves while allowing longitudinal wave
propagation as in “fluid-like” elasticity. This peculiar behavior, together with the complete …