| Autor: |
P.H. Otsuka, R. Chinbe, M. Tomoda, O. Matsuda, Y. Tanaka, D.M. Profunser, S. Kim, H. Jeon, I.A. Veres, A.A. Maznev, O.B. Wright |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Photoacoustics, Vol 31, Iss , Pp 100481- (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2213-5979 |
| DOI: |
10.1016/j.pacs.2023.100481 |
| Popis: |
We extend gigahertz time-domain imaging to a wideband investigation of the eigenstates of a phononic crystal cavity. Using omnidirectionally excited phonon wave vectors, we implement an ultrafast technique to experimentally probe the two-dimensional acoustic field inside and outside a hexagonal cavity in a honeycomb-lattice phononic crystal formed in a microscopic crystalline silicon slab, thereby revealing the confinement and mode volumes of phonon eigenstates—some of which are clearly hexapole in character—lying both inside and outside the phononic-crystal band gap. This allows us to obtain a quantitative measure of the spatial acoustic energy storage characteristics of a phononic crystal cavity. We also introduce a numerical approach involving toneburst excitation and the monitoring of the acoustic energy decay together with the integral of the Poynting vector to calculate the Q factor of the principal in-gap eigenmode, showing it to be limited by ultrasonic attenuation rather than by phonon leakage to the surrounding region. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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