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arXiv · 2203.05264

Suppression of Brillouin oscillation in transparent free-standing diamond thin films in picosecond ultrasound

Hsu Kai Weng·Akira Nagakubo·Hideyuki Watanabe·Hirotsugu Ogi
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Abstract

Brillouin oscillation appears in picosecond ultrasonics for a transparent specimen because of backward light scattering by moving strain pulse. Its amplitude is comparable with those of other responses, such as pulse-echo signals and through-thickness resonance, obscuring these non-Brillouin-oscillation responses. We here find that Brillouin oscillation can be suppressed in a transparent free-standing film by coating both sides with metallic thin film of appropriate thickness and that this peculiar behavior is caused by strain pulses generated on both sides with a slight phase difference. This phenomenon allowed us to fabricate a Brillouin-oscillation-free diamond free-standing film, which showed high capability for sensor applications.

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Hsu Kai Weng, Akira Nagakubo, Hideyuki Watanabe, Hirotsugu Ogi. 2022-03-10. Suppression of Brillouin oscillation in transparent free-standing diamond thin films in picosecond ultrasound. https://doi.org/10.1063/5.0087648

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