Optically excited nanoscale ultrasonic transducers

Smith, Richard J.; Cota, Fernando Perez; Marques, Leonel; Chen, Xuesheng; Arca, Ahmet; Webb, Kevin; Aylott, Jonathan W.; Somekh, Michael G.; Clark, Matt

Abstract

© 2015 Acoustical Society of America. In order to work at higher ultrasonic frequencies, for instance, to increase the resolution, it is necessary to fabricate smaller and higher frequency transducers. This paper presents an ultrasonic transducer capable of being made at a very small size and operated at GHz frequencies. The transducers are activated and read optically using pulsed lasers and without physical contact between the instrumentation and the transducer. This removes some of the practical impediments of traditional piezoelectric architectures (such as wiring) and allows the devices to be placed immediately on or within samples, reducing the significant effect of attenuation which is very strong at frequencies above 1 GHz. The transducers presented in this paper exploit simultaneous optical and mechanical resonances to couple the optical input into ultrasonic waves and vice versa. This paper discusses the mechanical and optical design of the devices at a modest scale (a few μm) and explores the scaling of the transducers toward the sub-micron scale. Results are presented that show how the transducers response changes depending on its local environment and how the resonant frequency shifts when the transducer is loaded by a printed protein sample.

Citation

Smith, R. J., Cota, F. P., Marques, L., Chen, X., Arca, A., Webb, K., …Clark, M. (2015). Optically excited nanoscale ultrasonic transducers. Journal of the Acoustical Society of America, 137(1), 219-227. https://doi.org/10.1121/1.4904487

• Journal Article Type: Article
• Acceptance Date: Nov 6, 2014
• Online Publication Date: Jan 23, 2015
• Publication Date: 2015-01
• Deposit Date: Jan 27, 2015
• Publicly Available Date: Jan 27, 2015
• Journal: Journal of the Acoustical Society of America
• Print ISSN: 0001-4966
• Electronic ISSN: 00001-4966
• Publisher: Acoustical Society of America
• Peer Reviewed: Peer Reviewed
• Volume: 137
• Issue: 1
• Pages: 219-227
• DOI: https://doi.org/10.1121/1.4904487
• Public URL: https://nottingham-repository.worktribe.com/output/742743
• Publisher URL: http://scitation.aip.org/content/asa/journal/jasa/137/1/10.1121/1.4904487?aemail=author
• Related Public URLs: http://scitation.aip.org/content/asa/journal/jasa
• Additional Information: Copyright 2015 Acoustical Society of America. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the Acoustical Society of America.; ; The following article appeared in The Journal of the Acoustical Society of Amer (Vol.137, No.1) and may be found at http://scitation.aip.org/content/asa/journal/jasa/137/1/10.1121/1.4904487?aemail=author.