Phononic dispersion in anisotropic pseudo-fractal hyper-lattices
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Published version
Author(s)
Fallah, AS
Navadeh, N
Tereshchuk, VV
Gorshkov, VN
Type
Journal Article
Abstract
Fractal and pseudo-fractal microstructures have proved promising in increasing the range of detectable frequencies for devices used in the realm of electromagnetism. Due to mechanical-electrical duality it is conjectured they may provide flexible solutions capable of closing/widening bandgaps and increasing tailorability in phononic lattices. Pseudo-fractal hyper-lattices have been considered in this work and different aspects of dispersion surface morphology and frequency band structure are studied. It has been observed that higher frequencies that can be excited in the simple square lattice are almost the same as those in the pseudo-fractal structures, however; through introduction of higher levels the pseudo-fractal hyper-lattice presents new features not observable in the ordinary lattice. By increasing the order of pseudo-fractal structure the number of degrees-of-freedom increases and dispersion surfaces morphologies change thus frequency gaps are eliminated. This phenomenon can be of advantage for acoustic/phononic visibility/detectability e.g. in designing sensors. In the classical analogy to quantum level repulsion surfaces flatten which sufficiently decreases the sound group velocity in the pseudo-fractal structure, and can be used for numerous practical applications.
Date Issued
2019-02-15
Date Acceptance
2018-12-19
Citation
Materials & Design, 2019, 164, pp.107560-107560
ISSN
0264-1275
Publisher
Elsevier BV
Start Page
107560
End Page
107560
Journal / Book Title
Materials & Design
Volume
164
Copyright Statement
© 2018 Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Subjects
0912 Materials Engineering
0913 Mechanical Engineering
Materials
Publication Status
Published
Article Number
107560
Date Publish Online
2018-12-22