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Tomographic reconstruction of picosecond acoustic strain pulses using automated angle-scan probing with visible light.

ABSTRACT: By means of an ultrafast optical technique, picosecond acoustic strain pulses in a transparent medium are tomographically visualized at GHz frequencies. The strain distribution in BK7 glass is reconstructed from time-domain reflectivity changes of 415-nm probe light as a function of the optical incidence angle with 1 ps temporal and 120 nm spatial resolutions, enabled by automated angle scanning. The latter resolution is achieved owing to the commensurate acoustic wavelength. Applications include imaging strain, carrier and temperature distributions on ultrashort timescales.

SUBMITTER: Tomoda M

PROVIDER: S-EPMC10665958 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Tomographic reconstruction of picosecond acoustic strain pulses using automated angle-scan probing with visible light.

Tomoda Motonobu M Matsuo Hiroyuki H Matsuda Osamu O Li Voti Roberto R Wright Oliver B OB

Photoacoustics 20231029

By means of an ultrafast optical technique, picosecond acoustic strain pulses in a transparent medium are tomographically visualized at GHz frequencies. The strain distribution in BK7 glass is reconstructed from time-domain reflectivity changes of 415-nm probe light as a function of the optical incidence angle with 1 ps temporal and 120 nm spatial resolutions, enabled by automated angle scanning. The latter resolution is achieved owing to the commensurate acoustic wavelength. Applications includ ...[more]

PMID: 38027528

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