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Phononic crystal as a neutron detector
Ultrasonics, 2019A perfect phononic crystal model composed of concrete and epoxy, and another defect model of Aluminum/Concrete/Epoxy were proposed. The two models were analyzed computationally and theoretically based on the transfer matrix method. The proposed models were capable of detecting and sensing neutrons irradiations over a wide fluence range based on the ...
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Tunable Phononic Crystals and Metamaterials
2012The objective of this chapter is to show how it would be possible to introduce a certain degree of tunability of the properties of phononic crystals. The main concepts underlying the conception of tunable phononic crystals are first introduced with simple models: the one-dimensional harmonic crystal with varying parameter and two coupled one ...
Bou Matar, Olivier +2 more
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2012
This chapter presents a comprehensive description of the properties of phononic crystals ranging from spectral properties (e.g., band gaps) to wave vector properties (refraction) and phase properties. These properties are characterized by experiments and numerical simulations.
Sukhovich, A. +5 more
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This chapter presents a comprehensive description of the properties of phononic crystals ranging from spectral properties (e.g., band gaps) to wave vector properties (refraction) and phase properties. These properties are characterized by experiments and numerical simulations.
Sukhovich, A. +5 more
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Theory of phonon-phonon interactions in molecular crystals
Journal de Chimie Physique, 1985Some aspects of the theory of phonon-phonon interactions in molecular crystals are developed. Attention is restricted to rigid molecule vibrations. The orientational kinetic energy of a molecule Is expressed In terms of conjugate coordinates and momenta, derived from quaternions.
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Phonon Images and Phonon Conduction in Trigonal Crystals
1989Monte Carlo phonon-focusing patterns provide graphic illustration of the striking changes in phonon intensity arising from elastic anisotropy and piezoelectric coupling. Patterns for each of the three modes show the basic acoustic symmetry of the crystal and suggest crystallographic directions along which enhanced phonon conductivity can be expected in
A. K. McCurdy, A. G. Every
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Future Prospects of Phononic Crystals and Phononic Metamaterials
2016The principles of operation of phononic crystal structures hold in a variety of frequency ranges starting from a portion of 1 Hertz to a few Tera Hertz. Therefore, phononic crystal structures can be beneficial for a variety of applications at different ranges of frequencies using various configurations and regimes of operation.
Saeed Mohammadi +2 more
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Journal of Physics: Condensed Matter, 1991
The simple example of phonons in a linear chain of atoms with substitutional disorder is reconsidered in order to determine the rearrangements of acoustic and localized mode branches with increasing concentration of light impurities. The coherent-potential approximation cannot be applies successfully to this problem.
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The simple example of phonons in a linear chain of atoms with substitutional disorder is reconsidered in order to determine the rearrangements of acoustic and localized mode branches with increasing concentration of light impurities. The coherent-potential approximation cannot be applies successfully to this problem.
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Dynamic visualization of surface phonons in phononic crystals
2011Using ultrashort pulsed optical excitation and interferometric detection, we dynamically image ultrahigh-frequency surface acoustic phonon wavepackets on two-dimensional (2D) phononic crystals. The samples consist of a square lattice of air-filled holes etched in a silicon substrate. Good agreement is found when compared with time-domain finite element
Wright, O. B. +5 more
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