The Experts below are selected from a list of 82896 Experts worldwide ranked by ideXlab platform
Anthony C Zander - One of the best experts on this subject based on the ideXlab platform.
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interaction of a flow excited helmholtz resonator with a grazing turbulent boundary layer
Experimental Thermal and Fluid Science, 2014Co-Authors: Farzin Ghanadi, Maziar Arjomandi, B Cazzolato, Anthony C ZanderAbstract:This study focuses on the characteristics of the flow oscillations induced by various Helmholtz Resonators which are excited by a fully developed turbulent grazing flow. A full experimental investigation has been conducted in a subsonic wind tunnel with a low turbulence level. Detailed fluid dynamic and acoustic analyses of the flow inside the wall-mounted resonator and within the shear layer have been performed. The results reveal that the degree of excitation of the pressure and velocity fields is related to the resonator geometry, and that the pressure fluctuations within the resonator are most sensitive to the orifice length for the range of geometric parameters considered. Interestingly, the turbulent length scale over the orifice with the minimum diameter was found to be higher than the other cases investigated. This in turn causes a modification to the turbulent structures downstream of the resonator. The turbulence intensity and energy spectra of the velocity fluctuations within the turbulent boundary layer downstream of the Resonators demonstrate that in a specific velocity range certain Resonators have the potential to modify the flow instabilities within the turbulent boundary layer. The results provide information on the relationship between the pressure and velocity fluctuations within and downstream of the resonator and the geometric characteristics of the resonator and the properties of the grazing flow.
Ran Fischer - One of the best experts on this subject based on the ideXlab platform.
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spin detection with a micromechanical trampoline towards magnetic resonance microscopy harnessing cavity optomechanics
New Journal of Physics, 2019Co-Authors: Ran Fischer, Dylan P Mcnally, Chris Reetz, Gabriel G T Assumpcao, Thomas R KniefAbstract:We explore the prospects and benefits of combining the techniques of cavity optomechanics with efforts to image spins using magnetic resonance force microscopy (MRFM). In particular, we focus on a common mechanical resonator used in cavity optomechanics—high-stress stoichiometric silicon nitride (Si3N4) membranes. We present experimental work with a 'trampoline' membrane resonator that has a quality factor above 106 and an order of magnitude lower mass than a comparable standard membrane Resonators. Such high-stress Resonators are on a trajectory to reach 0.1 force sensitivities at MHz frequencies by using techniques such as soft clamping and phononic-crystal control of acoustic radiation in combination with cryogenic cooling. We present a demonstration of force-detected electron spin resonance of an ensemble at room temperature using the trampoline Resonators functionalized with a magnetic grain. We discuss prospects for combining such a resonator with an integrated Fabry–Perot cavity readout at cryogenic temperatures, and provide ideas for future impacts of membrane cavity optomechanical devices on MRFM of nuclear spins.
Sridhar Krishnaswamy - One of the best experts on this subject based on the ideXlab platform.
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polymer micro ring resonator integrated with a fiber ring laser for ultrasound detection
Optics Letters, 2017Co-Authors: Heming Wei, Sridhar KrishnaswamyAbstract:Polymer micro-ring Resonators fabricated by a direct laser writing technique are presented as sensors for ultrasound detection. The optical micro-ring resonator consists of a micro-ring waveguide that acts as a wavelength selective feedback mirror to an erbium-doped fiber-ring laser (FRL). The micro-ring resonator reflection spectrum determines the lasing frequencies of the FRL. Acoustic waves, which cause strain or deformation of the micro-ring resonator, lead to shifts of the resonance wavelength and thereby shifts in the FRL lasing spectrum. The spectral shifts are demodulated using an unbalanced Michelson interferometer. The experiments demonstrate that polymer micro-ring Resonators integrated with a FRL can be used as adaptive high-frequency ultrasound detectors.
Humberto Campanella - One of the best experts on this subject based on the ideXlab platform.
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a high impedance dual mode saw resonator for ultra low power and high data rate fsk modulator
Sensors and Actuators A-physical, 2014Co-Authors: Yao Zhu, Yuanjin Zheng, Chengliang Sun, Yuan Gao, Humberto CampanellaAbstract:Abstract This paper reports on the design and experimental realization of a dual-mode surface acoustic wave (SAW) resonator with two high-impedance resonant peaks for ultra low power binary frequency-shift-keying (FSK) modulator applications. The single-device structure of the dual-mode resonator is believe to be a promising solution to eliminate the loading effect and noise as a result of multiple switches and other parallel connected Resonators, and has the potential to reduce the size and complexity of packaging, compared with the multi-resonator multi-frequency approaches. The dual-mode SAW resonator concept is realized by an in-house, two-mask process that delivered symmetric-mode Resonators at 404.9 MHz with trans-impedance values of 1,100 Ω and quality factor of 3134, and anti-symmetric mode Resonators at 407.6 MHz, with 900 Ω trans-impedance and 4014 quality factors. Based on the experimental results, we propose a FSK modulator that integrates this high-transimpedance dual-mode resonator and reaches data rates up to 1.5 Mbps. The FSK modulator can be used for low power transmitters in body area network (BAN) and wireless sensor networks (WSN).
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acoustic wave and electromechanical Resonators concept to key applications
2010Co-Authors: Humberto CampanellaAbstract:Preface Part I: Introduction to Thin-Film Bulk Acoustic Wave Resonators (FBAR), Micro and Nano Electro Mechanical System (M/NEMS) Resonators - MEMS and NEMS Resonator Technologies Acoustic Resonator Technologies Design and Modeling of Micro and Nano Resonators Part II: Fabrication Technologies and CMOS Integration - Fabrication Techniques Characterization Techniques Performance Optimization Integration of Resonator to CMOS Technologies Part III: Applications of FBAR, MEMS, NEMS Resonators - Sensor Applications Radio Frequency (RF) Applications Case Studies: Modeling, Design and Fabrication of FBAR and MEMS-Based Systems.
Songcheol Hong - One of the best experts on this subject based on the ideXlab platform.
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a transmitter or a receiver consisting of two strongly coupled Resonators for enhanced resonant coupling in wireless power transfer
IEEE Transactions on Industrial Electronics, 2014Co-Authors: Dukju Ahn, Songcheol HongAbstract:This paper proposes a novel resonator structure for efficiency and transferred power improvements: a transmitter (a receiver) that consists of two strongly coupled Resonators. The two strongly coupled Resonators are embedded within a transmitter device (a receiver device) and behave as a single resonator with enhanced performances. Unlike the conventional four-coil system, the first and the fourth Resonators are also designed to have high loaded-Q and maximum cross couplings. Therefore, the first and the fourth Resonators also take part in the coupled resonance with opposite-side Resonators. This provides additional energy exchange path. The exact design guidelines are provided for each different resonance topology from analytical derivation. It is analyzed and experimentally demonstrated that the efficiency and the transferred power are increased by the proposed two-resonator technique. For a 30 cm × 25 cm parallel-resonant transmitter and an 18 cm × 16 cm parallel-resonant receiver at 13-cm distance, the efficiency and the transferred power with the proposed technique are 65.2% and 17.2 W, respectively, whereas those values without the proposed technique are only 37.3% and 6.2 W.
