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arXiv · 1909.08858

Ultimate Photo-Thermo-Acoustic Efficiency of Graphene Aerogels

Francesco De Nicola·Lorenzo Donato Tenuzzo·Ilenia Viola·Rujing Zhang·Hongwei Zhu·Augusto Marcelli·Stefano Lupi
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Abstract

The ability to generate, amplify, mix, and modulate sound with no harmonic distortion in a passive opto-acoustic device would revolutionize the field of acoustics. The photo-thermo-acoustic (PTA) effect allows to transduce light into sound without any bulk electro-mechanically moving parts and electrical connections, as for conventional loudspeakers. Also, PTA devices can be integrated with standard silicon complementary metal-oxide semiconductor (CMOS) fabrication techniques. Here, we demonstrate that the ultimate PTA efficiency of graphene aerogels, depending on their particular thermal and optical properties, can be experimentally achieved by reducing their mass density. Furthermore, we illustrate that the aerogels behave as an omnidirectional point-source throughout the audible range with no harmonic distortion. This research represents a breakthrough for audio-visual consumer technologies and it could pave the way to novel opto-acoustic sensing devices.

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Francesco De Nicola, Lorenzo Donato Tenuzzo, Ilenia Viola, Rujing Zhang, Hongwei Zhu, Augusto Marcelli, Stefano Lupi. 2019-09-19. Ultimate Photo-Thermo-Acoustic Efficiency of Graphene Aerogels. https://doi.org/10.1038/s41598-019-50082-7

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