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Showing 1 to 14 of 14 for “"Phononic crystal"”.
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Gallium Nitride phononic crystal resonator
… Nitride (GaN) Lamb Wave resonator using a Phononic Crystal (PnC) to selectively confine elastic vibrations with wide-band spurious mode suppression. A unique feature of the design demonstrated here is a folded PnC structure to relax energy confinement in the non-resonant dimension and to …
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Ultra-sensitive Mid-infrared Detection Using Phononic Crystal Resonator-based Oscillator
… detectors based on surface acoustic wave (SAW) phononic crystal (PnC) oscillators. By configuring a PnC resonator featuring high-frequency-quality-factor product into a low-noise self-oscillation system, my MIR detector achieves high sensitivity on the order of hundreds of picowatts. The SAW …
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Modeling and characterization of elastic wave propagation in micro-scale photonic crystals
Micro-scale phononic crystals are micro-electro-mechanical-systems (MEMS) made of one material periodically embedded in another material, leading to periodic changes in elastic properties of the composite structure. Such devices exhibit elastic bandgaps, which are very useful in many commercial …
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Investigating the Existence of Coherent Phonon Scattering in Silicon Using Phononic Crystals
… of phonons scattered from the inclusions in the phononic crystal. The intent of this work is to investigate the existence of coherent scattering in Si via phononic crystals. A phononic crystal is a periodic array of inclusions inside a host material. The inclusions could be a second material or a …
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Wave Motion in 1-D Viscoelastic Phononic Crystals: A Comprehensive Analytical, Numerical and Experimental Study
Phononic crystals are engineered materials which exhibit unique wave motion properties due to periodic arrangement of multiple homogeneous constituents. Over the last decade, metallic phononic crystals have been thoroughly investigated. However, viscoelastic phononic crystals composed of polymers …
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Acoustic Bragg reflectors for Q-enhancement of unreleased MEMS resonators
… that the ABR is more favorable than the phononic crystal for acoustic energy localization for unreleased resonators, providing a 9 times higher Q.
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High Yield Fabrication of Monolayer WSe₂ Mechanical Resonators and a Study of Their Loss Mechanisms
… at cryogenic temperatures through the use of phononic shielding. I compare the results of measured quality factors from experiments done on 2.5 µm diameter and 5 µm resonators samples on TEM grid membranes to 4 µm diameter resonator samples utilising phononic shielding through the use of …
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Optimal wavefronts and subwavelength structures : computer-aided design for optics and acoustics
… characterization results of a photonic crystal solar absorber with wide-angle spectral selectivity. Next, we discuss a multiscale acoustic model of a phononic crystal with strong spatial dispersion. We are optimistic that our computational frameworks for wavefronts and subwavelength …
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Monolithically integrated MEMS resonators and oscillators in standard IC technology
… active field-effect-transistor (FET) sensing. A phononic crystal (PnC) implemented in the CMOS back-end-of-line (BEOL) layers along with the bulk wafer are used to create a phononic waveguide. The latter confines acoustic vibrations in the CMOS front-end-of-line (FEOL) layers. Operator-theoretic …
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Guiding of plasmons and phonons in complex three dimensional structures
… Such structures represent a three-dimensional “phononic crystal” but affect heat flow instead of acoustics. The thermal conductivity of inverse opal films are relatively low, ~0.6-1.4 W/mK at 300 K which is due to macroscopic bending of heat flow lines in the structure. The corresponding …
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Generalized phononic networks : of length scales, symmetry breaking and (non) locality : "controlling complexity through simplicity"
… from sound insulation to heat management. Phononic crystals and metamaterials are artificially structured materials (at certain length scales) that provide promise in controlling the propagation of phonons in solids. However, the vector nature of the phonon makes the development of a …
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Observation of mechanical bound states in the continuum
Phonon trapping has raised widespread attention among researchers for its potential of various applications, such as microwave signal processing, interferometric gravitational wave detection and quantum mechanical oscillators. A common way to realize phonon trapping is through suspended structures …
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Mechanical bound states in the continuum in phononic crystals
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2026-08-01
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Release-free silicon optomechanical devices with Bound-state In the Continuum
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2025-05-01