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arXiv · 1806.03930

High Efficiency and Low Distortion Photoacoustic Effect in 3D Graphene Sponge

Flavio Giorgianni·Carlo Vicario·Mostafa Shalaby·Lorenzo Donato Tenuzzo·Augusto Marcelli·Tengfei Zhang·Kai Zhao·Yongsheng Chen·Christoph Hauri·Stefano Lupi
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Abstract

The conversion of light in sound plays a crucial role in spectroscopy, applied physics, and technology. In this paper, light sound conversion in 3D graphene sponge through a photothermoacoustic mechanism is reported. It is shown that the unique combination of mechanical, optical, and thermodynamic properties of graphene assembled in a 3D sponge structure allows an unprecedented high efficiency conversion independent of light wavelength from infrared to ultraviolet. As a first application of this effect, a photothermal based graphene sponge loudspeaker is demonstrated, providing a full digital operation for frequencies from acoustic to ultrasound. The present results suggest a new pathway for light generation and control of sound and ultrasound signals potentially usable in a variety of new technological applications from high fidelity loudspeaker and radiation detectors to medical devices.

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Flavio Giorgianni, Carlo Vicario, Mostafa Shalaby, Lorenzo Donato Tenuzzo, Augusto Marcelli, Tengfei Zhang, Kai Zhao, Yongsheng Chen, Christoph Hauri, Stefano Lupi. 2018-06-11. High Efficiency and Low Distortion Photoacoustic Effect in 3D Graphene Sponge. https://doi.org/10.1002/adfm.201702652

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