Skip to Main content Skip to Navigation
Journal articles

Three-dimensional elasto-optical interaction for reflectometric detection of diffracted acoustic fields in picosecond ultrasonics

Abstract : The three-dimensional 3D photoelastic interaction involved in the detection mechanism of picosecond ultrasonics is investigated in micrometric metallic films. In pump-probe experiments, the laser source beam is focused to a spot size of less than 1 μm. A 3D diffracted acoustic field is generated at high frequencies of several tens of gigahertz, containing longitudinal and shear waves altogether. Their propagation changes the dielectric permittivity tensor and the material becomes optically heterogeneous. Consequently, the detection process is modeled through the propagation of the laser probe beam in a material with dielectric properties varying in all directions. Thus, the solution of Maxwell's equations leads to a differential system, the source term of which is proportional to the acoustic field itself. In the frame of small perturbation theory, the latter is decomposed into a continuous sum of monochromatic plane waves. The scattered electromagnetic field is described using the matricant, and the ensuing analytical solution then allows analyzing the 3D photoelastic interaction. The contribution of acoustic diffraction and shear wave detection to the reflectometric signal is put into relief. Good agreement with experiments performed in a 1 μm thick aluminum film is found.
Complete list of metadatas

Cited literature [3 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-01658485
Contributor : Thomas Dehoux <>
Submitted on : Thursday, December 7, 2017 - 4:13:09 PM
Last modification on : Friday, April 24, 2020 - 10:28:07 AM

File

Dehoux2007_v76_p024311.pdf
Publisher files allowed on an open archive

Identifiers

Citation

Thomas Dehoux, Nikolay Chigarev, Clément Rossignol, Bertrand Audoin. Three-dimensional elasto-optical interaction for reflectometric detection of diffracted acoustic fields in picosecond ultrasonics. Physical Review B: Condensed Matter and Materials Physics, American Physical Society, 2007, 76 (2), pp.024311. ⟨10.1103/PhysRevB.76.024311⟩. ⟨hal-01658485⟩

Share

Metrics

Record views

306

Files downloads

483