Institute of Multidisciplinary Research for Advanced Materials, Tohoku University


LAST UPDATE 2021/05/20

  • 研究者氏名
    Researcher Name

    上杉祐貴 Yuuki UESUGI
    助教 Assistant Professor
  • 所属
    Professional Affiliation

    Institute of Multidisciplinary Research for Advanced Materials, Tohoku University

    プロセスシステム工学研究部門 光物質科学研究分野
    Division of Process and System Engineering, Laser Applied Material Science
  • 研究キーワード
    Research Keywords

    Optical cavity
    High-intensity lasers fields
    Laser-Compton scattering
    Absorption spectroscopy
Research Subject
Development of self-resonating optical cavity system and its applications

研究の背景 Background


An optical cavity is highly sensitive device which can increase the interaction length of laser light through material by more than 10,000 times. It is used for precision measurement of an optical phase difference like gravitational-wave detectors, high-sensitive absorption spectroscopy, experiments of the vacuum birefringence measurement and so on. Furthermore, the cavity is also utilized for accumulating laser light in it to produce high-intensity laser fields.

研究の目標 Outcome


Recently, we demonstrated a highly stable optical cavity, the “Feedback-free cavity”, which overcomes a problem that conventional cavities are too delicate to treat in environment noise. We aim to expand the laboratory-based applications of the cavities, like precision measurement or laser power storage, into utilization in industrial and medical fields.

研究図Research Figure

Fig.1. A conceptual diagram of the feedback-free cavity with self-resonating mechanism. The laser amplifier (Amp.) amplifies the leaked light from the optical cavity. Therefore, the light frequency always satisfies the resonance condition of the cavity regardless of the fluctuation of the cavity length. Fig.2. a) An ultra-high reflectivity mirror. b) A frame body of the cavity. c) The measured lifetime of the optical cavity. The finesse of the cavity was 646,000. Fig.3. The transmitted light power from the cavity. a, b) The resonance was broken by strong mechanical shock. c) The resonance was stable in environment noise.

文献 / Publications

arXiv:1610.03141v1 (2016). APL Photonics 1, 026103 (2016). Rev. Sci. Inst. 86, 043303 (2015). Nucl. Instrum. Meth. B 319, 17-23 (2014).