Probing gigahertz coherent acoustic phonons in TiO2 mesoporous thin films

Ultrahigh-frequency acoustic-phonon resonators usually require atomically flat interfaces to avoid phonon scattering and dephasing, leading to expensive fabrication processes, such as molecular beam epitaxy. Mesoporous thin films are based on inexpensive wet chemical fabrication techniques that lead...

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Detalles Bibliográficos
Autores: Cardozo de Oliveira, E. R., Xiang, C., Esmann, M., López Abdala, Nicolás Andrés, Fuertes, María Cecilia, Bruchhausen, Axel Emerico, Pastoriza, Hernan, Perrin, B., Soler Illia, Galo Juan de Avila Arturo, Lanzillotti Kimura, N. D.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/220087
Acceso en línea:http://hdl.handle.net/11336/220087
Access Level:acceso abierto
Palabra clave:ACOUSTIC PHONONS
ACOUSTIC RESONATORS
ACOUSTICS MULTILAYERS
COHERENT PHONONS
MESOPOROUS THIN FILMS
PICOSECOND ULTRASONICS
PUMP-PROBE
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descripción
Sumario:Ultrahigh-frequency acoustic-phonon resonators usually require atomically flat interfaces to avoid phonon scattering and dephasing, leading to expensive fabrication processes, such as molecular beam epitaxy. Mesoporous thin films are based on inexpensive wet chemical fabrication techniques that lead to relatively flat interfaces regardless the presence of nanopores. Here, we report mesoporous titanium dioxide-based acoustic resonators with resonances up to 90 GHz, and quality factors from 3 to 7. Numerical simulations show a good agreement with the picosecond ultrasonics experiments. We also numerically study the effect of changes in the speed of sound on the performance of the resonator. This change could be induced by liquid infiltration into the mesopores. Our findings constitute the first step towards the engineering of building blocks based on mesoporous thin films for reconfigurable optoacoustic sensors.