Abstract
We investigate the interaction of guided surface acoustic modes (GSAMs) in unconsolidated granular media with a metasurface, consisting of an array of vertical oscillators. We experimentally observe the hybridization of the lowest-order GSAM at the metasurface resonance, and note the absence of mode delocalization found in homogeneous media. Our numerical studies reveal how the stiffness gradient induced by gravity in granular media causes a down-conversion of all the higher-order GSAMs, which preserves the acoustic energy confinement. We anticipate these findings to have implications in the design of seismic-wave protection devices in stratified soils.
Original language | English (US) |
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Article number | 054026 |
Journal | Physical Review Applied |
Volume | 9 |
Issue number | 5 |
DOIs | |
State | Published - May 17 2018 |
ASJC Scopus subject areas
- General Physics and Astronomy