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arXiv · 1910.08765

Experimental Observation of Nonreciprocal Waves in a Resonant Metamaterial Beam

M. A. Attarzadeh·J. Callanan·M. Nouh
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Abstract

Space-time-varying materials pledge to deliver nonreciprocal dispersion in linear systems by inducing an artificial momentum bias. Although such a paradigm eliminates the need for actual motion of the medium, experimental realization of space-time structures with dynamically changing material properties has been elusive. In this letter, we present an elastic metamaterial that exploits stiffness variations in an array of geometrically phase-shifted resonators -- rather than external material stimulation -- to induce a temporal modulation. We experimentally demonstrate that the resulting bias breaks time-reversal symmetry in the resonant metamaterial, and achieves a nonreciprocal tilt of dispersion modes within dynamic modulation regimes.

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M. A. Attarzadeh, J. Callanan, M. Nouh. 2019-10-19. Experimental Observation of Nonreciprocal Waves in a Resonant Metamaterial Beam. https://doi.org/10.1103/physrevapplied.13.021001

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