Mesoporous Thin Films for Acoustic Devices in the Gigahertz Range

ABDALA, NICOLAS LOPEZ; ESMANN, MARTIN; FUERTES, MARIA C.; ANGELOMÉ, PAULA C.; ORTIZ, OMAR; BRUCHHAUSEN, AXEL; PASTORIZA, HERNAN; PERRIN, BERNARD; SOLER-ILLIA, GALO J. A. A.; LANZILLOTTI-KIMURA, NORBERTO D.

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2020 vol. 124 p. 17165 - 17171

1932-7447

The coherent manipulation of acoustic waves on the nanoscale usually requiresmultilayers with thicknesses and interface roughness defined down to the atomic monolayer. This resultsin expensive devices with predetermined functionality. Nanoscale mesoporous materials present highsurface-to-volume ratio and tailorable mesopores, which allow the incorporation of chemicalfunctionalization to nanoacoustics. However, the presence of pores with sizes comparable to the acousticwavelength is intuitively perceived as a major roadblock in nanoacoustics. Here we present multilayerednanoacoustic resonators based on mesoporous SiO2 thin-films showing acoustic resonances in the 5-100GHz range. We characterize the acoustic response of the system using coherent phonon generationexperiments. Despite resonance wavelengths comparable to the pore size, we observe for the first timewell-defined acoustic resonances. Our results open the path to a promising platform for nanoacousticsensing and reconfigurable acoustic nanodevices based on soft, inexpensive fabrication methods.