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Spatiotemporal path discontinuities of wavepackets propagating across a meta-atom.

ABSTRACT: The realization of phase discontinuities across metasurfaces has led to a new class of reflection and refraction. Here we present theory and experiment on the discontinuous propagation of wavepackets across subwavelength-thickness meta-atoms. Using acoustic waves, we observe the process of wavepackets traversing a meta-atom with abrupt displacements, which appear as path discontinuities on a space-time diagram. We construct a tunable meta-atom from two coupled resonators at ~500 Hz, map the spatiotemporal trajectories of individual sonic pulses, and reveal discontinuities at the meta-atom where the pulses exit at a time ~50 ms ahead or behind their arrivals. Applications include thin acoustic metasurface lenses.

SUBMITTER: Yoo I

PROVIDER: S-EPMC3985075 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Spatiotemporal path discontinuities of wavepackets propagating across a meta-atom.

Yoo Insang I Han Chung Kyu CK Shin Dong-Soo DS Lee K J B KJ Wu J W JW Moon Han Seb HS Wright Oliver B OB Lee Sam H SH

Scientific reports 20140414

The realization of phase discontinuities across metasurfaces has led to a new class of reflection and refraction. Here we present theory and experiment on the discontinuous propagation of wavepackets across subwavelength-thickness meta-atoms. Using acoustic waves, we observe the process of wavepackets traversing a meta-atom with abrupt displacements, which appear as path discontinuities on a space-time diagram. We construct a tunable meta-atom from two coupled resonators at ~500 Hz, map the spat ...[more]

PMID: 24728015

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