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Research into properties of heterogeneous artificial materials, consisting of arrangements of rigid scatterers embedded in a medium with different elastic properties, has been intense throughout last two decades. The capability to prevent the transmission of waves in predetermined bands of frequencies -called bandgaps- becomes one of the most interesting properties of these systems, and leads to the possibility of designing devices to control wave propagation. The underlying physical mechanism is destructive Bragg interference. Here we show a technique that enables the creation of a wide bandgap in these materials, based on fractal geometries. We have focused our work in the acoustic case where these materials are called Phononic/Sonic Crystals (SC) but, the technique could be applied any types of crystals and wave types in ranges of frequencies where the physics of the process is linear.
Mechanical metamaterials are architected manmade materials that allow for unique behaviors not observed in nature, making them promising candidates for a wide range of applications. Existing metamaterials lack tunability as their properties can only
We propose a new approach to the generation of acoustic frequency combs (AFC) -- signals with spectra containing equidistant coherent peaks. AFCs are essential for a number of sensing and measurement applications, where the established technology of
Laminar flow velocity profiles depend heavily on fluid rheology. Developing methods of laminar flow characterization, based on low-field magnetic resonance (MR), contributes to the widespread industrial application of the MR technique in rheology. In
Acoustic frequency combs leverage unique properties of the optical frequency comb technology in high-precision measurements and innovative sensing in optically inaccessible environments such as under water, under ground or inside living organisms. Be
The physics of foams and emulsions has traditionally been studied using bulk foam/emulsion tests and single film platforms such as the Scheludko cell. Recently there has been a renewed interest in a third class of techniques that we term as single bu