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arXiv · 1008.1473

Anomalous Microfluidic Phonons Induced by the Interplay of Hydrodynamic Screening and Incompressibility

Tsevi Beatus·Roy Bar-Ziv·Tsvi Tlusty
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Abstract

We investigate the acoustic normal modes ("phonons") of a 1D microfluidic droplet crystal at the crossover between 2D flow and confined 1D plug flow. The unusual phonon spectra of the crystal, which arise from long-range hydrodynamic interactions, change anomalously under confinement. The boundaries induce weakening and screening of the interactions, but when approaching the 1D limit we measure a marked increase in the crystal sound velocity, a sign of interaction strengthening. This non-monotonous behavior of the phonon spectra is explained theoretically by the interplay of screening and plug flow.

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Tsevi Beatus, Roy Bar-Ziv, Tsvi Tlusty. 2010-08-09. Anomalous Microfluidic Phonons Induced by the Interplay of Hydrodynamic Screening and Incompressibility. https://doi.org/10.1103/physrevlett.99.124502

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