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Resonance Frequency of Optical Microbubble Resonators: Direct Measurements and Mitigation of Fluctuations

Alessandro Cosci, Simone Berneschi, Ambra Giannetti, Daniele Farnesi, Franco Cosi, Francesco Baldini, Gualtiero Nunzi Conti, Silvia Soria, Andrea Barucci, Giancarlo Righini, Stefano Pelli
2016 Sensors  
A frequency fluctuation parameter σ was defined as a score of resonance stability and was evaluated in the presence and absence of the encaging system and in the case of air-or water-filling of the cavity  ...  This work shows the improvements in the sensing capabilities and precision of an Optical Microbubble Resonator due to the introduction of an encaging poly(methyl methacrylate) (PMMA) box.  ...  Nunzi Conti contributed in the data analysis and interpretation. S. Pelli directed the experiment. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s16091405 pmid:27589761 pmcid:PMC5038683 fatcat:k2fblqrcxba7dmmfh47vusq6we

Optical Microbottle Resonators for Sensing

Pablo Bianucci
2016 Sensors  
This has made them a well-established platform for highly sensitive physical, chemical, and biological sensors. Microbottle resonators (MBR) are a type of WGM optical microresonator.  ...  In this review, we discuss recent advances in the theory and fabrication of different kinds of MBRs, including hollow ones, and their application to optofluidic sensing.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s16111841 pmid:27827834 pmcid:PMC5134500 fatcat:7xqma35p2nf4fjl3wywuizvjmu

Biological Cell Resonators [article]

Jonathan M. M. Hall
2018 arXiv   pre-print
The gulf between modelling and biological resonators is bridged by an in-depth study of the physical characteristics of a range of biological cells, and the selection criteria for viable resonator candidates  ...  This thesis develops the theory of whispering gallery modes, exploring under what conditions a micro or nanoscale device can sustain these resonances, and for which physical criteria the resonance conditions  ...  To mitigate this effect, a combination of techniques is employed to maximise the likelihood of measuring WGMs in the embryo.  ... 
arXiv:1709.02534v2 fatcat:76mf6q5a7ffb7huqm5xdo7oxwu

Enhanced nanoparticle detection with liquid droplet resonators

M. R. Foreman, S. Avino, R. Zullo, H.-P. Loock, F. Vollmer, G. Gagliardi
2014 The European Physical Journal Special Topics  
Asymptotic formulae are derived for the relative resonance shift, line broadening and mode splitting of TE and TM modes in liquid droplet resonators.  ...  Experimental measurements of nanoparticle concentration based on whispering gallery mode resonance broadening are also presented.  ...  Naturally, cavity ring-down spectroscopy also permits a direct measurement of the optical loss in each WGM and thereby allows for a simple measurement of absorption and scattering cross sections [58]  ... 
doi:10.1140/epjst/e2014-02240-9 fatcat:taj3hvrkq5etbe3i4qrux3bmhy

The neural bases of normalising for accented speech: A repetition suppression functional magnetic resonance imaging study

Patti Adank, Peter Hagoort
2008 Journal of the Acoustical Society of America  
Presence vs. absence of a dip in intensity, duration of that dip, and degree of that dip in decibels are manipulated.  ...  Where the flap allophone of "t" and "d" is expected in American English, one frequently sees an approximant-like or even vocalic pattern, rather than a clear flap.  ...  It is shown that frequency spectra of fluctuations for these SHRUs have different predominating frequencies in accordance with mentioned directions of acoustic tracks.  ... 
doi:10.1121/1.2934685 fatcat:qqmjcl5gjzcj7kssv2pi6efwti

Ultrasound-Responsive Systems as Components for Smart Materials

Athanasios G. Athanassiadis, Zhichao Ma, Nicolas Moreno-Gomez, Kai Melde, Eunjin Choi, Rahul Goyal, Peer Fischer
2021 Chemical Reviews  
Ultrasound can carry energy safely and with low losses through complex and opaque media. It can be localized to small regions of space and couple to systems over a wide range of time scales.  ...  The diversity of emerging techniques holds great promise for a wide range of smart capabilities supported by ultrasound and poses interesting questions for further investigations.  ...  Because of the distinct resonant frequencies of the different bubbles, the flow direction could be controlled by switching the excitation frequency.  ... 
doi:10.1021/acs.chemrev.1c00622 pmid:34767350 pmcid:PMC8915171 fatcat:vokzxwr4jjcghggq547fkzyg5i

Acoustofluidics: Theory and simulation of streaming and radiation forces at ultrasound resonances in microfluidic devices

Henrik Bruus
2009 Journal of the Acoustical Society of America  
In particular, the radiation force-induced motion of microparticles and microbubbles in a swept-frequency ultrasonic resonator is considered.  ...  Direct Magnetic Resonance Imaging measurements of dynamics of the liquid and the dissolved gas show that the motions of dissolved gas ͑freon-22, CHClF2͒ and liquid ͑water͒ can be very different during  ...  Extending the frequency range of a resonator to 1 Mhz would in principle allow measurement down to ϳ3 µm, but significant challenges arise due to the confounding effects of geometric scatter from larger  ... 
doi:10.1121/1.4783855 fatcat:cyftnzsenzempdbtk4dd2hzw5u

Whispering gallery mode sensors

Matthew R. Foreman, Jon D. Swaim, Frank Vollmer
2015 Advances in Optics and Photonics  
We present a comprehensive overview of sensor technology exploiting optical whispering gallery mode (WGM) resonances.  ...  Ultimately WGM sensors aim for real-world applications, such as measurements of force and temperature, or alternatively gas and biosensing.  ...  Fluctuations in the cavity frequency can then be read out continuously by direct measurement of the feedback error signal.  ... 
doi:10.1364/aop.7.000168 pmid:26973759 pmcid:PMC4786191 fatcat:chycqunw2vcfbpghh6w56tixwe

Microbulles et cellules acoustiques

Michiel Postema
2017 Zenodo  
, University of Bergen and Christian Michelsen Research AS.  ...  Acknowledgements This work has been supported by DFG Emmy Noether Programme (grant no. 38355133) and Engineering and Physical Sciences Research Council (EPSRC) (grant no. EP/F037025/1).  ...  x 2 s % x 2 0 þ 2v r 3 0 q ; ð8Þ where x s is the angular resonance frequency of the encapsulated microbubble, x 0 is the angular resonance frequency of a free (unencapsulated) microbubble of the same  ... 
doi:10.5281/zenodo.4770898 fatcat:fyi3wieylzfx5haxhrj7es5gmm

Emerging material systems for integrated optical Kerr frequency combs

Andre Kovach, Dongyu Chen, Jinghan He, Hyungwoo Choi, Adil Han Dogan, Mohammadreza Ghasemkhani, Hossein Taheri, Andrea Armani
2020 Advances in Optics and Photonics  
This paper reviews the latest achievements in frequency comb generation using resonant cavities, placing them within the broader historical context of the field.  ...  The remaining challenges and future outlook for the field of cavity-based frequency combs is evaluated.  ...  figures and images.  ... 
doi:10.1364/aop.376924 fatcat:hj7ty2x7ivb6dfbq2n2nfkeprq

A design methodology for 2D sparse NDE arrays using an efficient implementation of refracted-ray TFM

Jerzy Dziewierz, Timothy Lardner, Anthony Gachagan
2013 2013 IEEE International Ultrasonics Symposium (IUS)  
Background, Motivation and Objective Developing new technologies that enable the repair or replacement of diseased or injured tissues and organs is a major focus of tissue engineering.  ...  Recent advances in the field of tissue engineering include the engineering of skin, cartilage, and bladder, all of which are relatively thin tissues that can rely on diffusion for the delivery of oxygen  ...  The authors acknowledge the ANR and DGA for their support under the project Metactif, grant ANR-11-ASTR-015.  ... 
doi:10.1109/ultsym.2013.0035 fatcat:th5znfh7y5bklfdbmhb4u6iq2i

Vocal fold vibratory and acoustic features in fatigued Karaoke singers

Gaowu Wang, Andy Lo, Karen Chan, Jiangping Kong, Edwin Yiu
2012 Journal of the Acoustical Society of America  
The Complex-modulus can then be determined at resonant frequencies. Some rigid viscoelastic rods are measured and the measured results agree well with that of commercial viscoelastic instrument.  ...  Whereafter the sonic response experiment for this structure is carried out, and the resonance frequency and root mean square (RMS) stress are measured.  ...  One group of participants learned to segregate concurrent vowels by using difference in fundamental frequency (ƒ 0 ) while the other group learned to use difference in sound location.  ... 
doi:10.1121/1.4708731 fatcat:cu5chvstgjbzhlhdzd63flz7nu

The influence of thresholding passive bubble-acoustic signals on the quantification of physical effects

Richard Manasseh, Yonggang Zhu, Hubert Chanson, Andrew Ooi, Alexander Babanin, Irena Bobevski
2012 Journal of the Acoustical Society of America  
The Complex-modulus can then be determined at resonant frequencies. Some rigid viscoelastic rods are measured and the measured results agree well with that of commercial viscoelastic instrument.  ...  Whereafter the sonic response experiment for this structure is carried out, and the resonance frequency and root mean square (RMS) stress are measured.  ...  One group of participants learned to segregate concurrent vowels by using difference in fundamental frequency (ƒ 0 ) while the other group learned to use difference in sound location.  ... 
doi:10.1121/1.4708757 fatcat:4zx4vkq66rgihgir2kv6pms4ea

Grafting acoustic instruments and signal processing: Creative control and augmented expressivity

Dan Overholt
2013 Journal of the Acoustical Society of America  
In addition, various measurement techniques for this type of space are explored and reported. 9:15 1aAA2. The effect of two different rooms on acoustical and perceptual measures of mixed choir sound.  ...  To achieve this, measurements of reverberation time and support factor of each space are coupled with participant surveys in 10 different Sacred Harp singing locations.  ...  In these experiments, the radiation force is applied to a gas microbubble produced by laser-induced optical breakdown, while displacement of the microbubble is measured by high-frequency ultrasound as  ... 
doi:10.1121/1.4830794 fatcat:2sexsmbypjcozjctnorzoiy7te

Current Development and Applications of Super-Resolution Ultrasound Imaging

Qiyang Chen, Hyeju Song, Jaesok Yu, Kang Kim
2021 Sensors  
Future directions and challenges to overcome for clinical translations are also discussed.  ...  Abnormal changes of the microvasculature are reported to be key evidence of the development of several critical diseases, including cancer, progressive kidney disease, and atherosclerotic plaque.  ...  Several imaging modalities, including microcomputed tomography (micro-CT) [11, 12] , optical coherence tomography (OCT) [13, 14] , and magnetic resonance imaging (MRI) [15] [16] [17] [18] [19] , have  ... 
doi:10.3390/s21072417 pmid:33915779 fatcat:mj7mtipezbg4nmretbdaoi6bhe
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