2019年第66回応用物理学会春季学術講演会

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一般セッション(ポスター講演)

22 合同セッションM 「フォノンエンジニアリング」 » 22.1 合同セッションM 「フォノンエンジニアリング」

[9a-PA3-1~10] 22.1 合同セッションM 「フォノンエンジニアリング」

2019年3月9日(土) 09:30 〜 11:30 PA3 (屋内運動場)

09:30 〜 11:30

[9a-PA3-4] Detecting sub-terahertz mechanical oscillations by a GaAs MEMS thermal sensor

Ya Zhang1,2、Shaoqing Du2、Boqi Qiu2、Kazuhiko Hirakawa2 (1.Tokyo University of Agriculture and Technology、2.University of Tokyo)

キーワード:phonon transport, MEMS, phonon interference

In this research, we propose a novel method to perform phonon spectroscopy of the heat transport process. We illuminate a GaAs MEMS suspended beam structure with two light pulses from a femtosecond (fs) laser. The generated phonons by the laser pulses propagate through the GaAs beam, and interfere with each other. We measure the phonon interference signal as the temperature rise on the beam by measuring the frequency shift of the MEMS resonator . If coherent phonon transfers exist in the beam, the temperature rise will have a dependence on the time delay between two light pulses, showing a phonon interference pattern. By performing a Fourier transform for the interference signal, we will obtain the phononic spectrum of the heat transport process. Our preliminary result shows that the temperature rise increases when the two laser pulses have a zero time delay, which is a typical feature of the phonon interference. The proposed method is very promising for realizing the ultra-fast phonon spectroscopy of heat transport process.