Direct measurement of mirror coating thermal noise for improving the sensitivity of gravitational wave detectors

• Project/Area Number: 15H05447
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: Aso Yoichi 国立天文台, 重力波プロジェクト推進室, 准教授 (10568174)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥20,020,000 (Direct Cost: ¥15,400,000、Indirect Cost: ¥4,620,000); Fiscal Year 2017: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000); Fiscal Year 2016: ¥8,060,000 (Direct Cost: ¥6,200,000、Indirect Cost: ¥1,860,000); Fiscal Year 2015: ¥9,230,000 (Direct Cost: ¥7,100,000、Indirect Cost: ¥2,130,000)
• Keywords: 重力波 / 熱雑音 / 誘電体多層膜コーティング / 宇宙物理 / 量子エレクトロニクス / 応用光学・量子光工学

Outline of Final Research Achievements

In this project, we worked on developing a system to directly measure coating thermal noise at low temperatures quickly and with high accuracy. Since the first direct detection of gravitational wave, the gravitational
wave astronomy has expanded rapidly. In order to further improve the detector sensitivity, we need to reduce the coating thermal noise, which limits the sensitivity around 100Hz. In order to select good coating technology for cryogenic interferometers like KAGRA, we have been developing a coating thermal noise measurement system utilizing cryogenic optical cavities. Through the analysis of elastic deformation of the cavities by seismic vibrations, optimization of optical design and so on, we have designed the system. We then constructed a cryostat, optical cavities made of monocrystalline silicon, input optics system and so on.

Research Products

• [Journal Article] Calculation method for light scattering caused by multilayer coated mirrors in gravitational wave detectors (2017)
  • Author(s): Simon Zeidler, Tomotada Akutsu, Yasuo Torii, Eiichi Hirose, Yoichi Aso, and Raffaele Flaminio
  • Journal Title: Optics express Volume: 23 Pages: 4741-4760
  • DOI: 10.1364/oe.25.004741
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Direct measurement of optical-trap-induced decoherence (2016)
  • Author(s): Nobuyuki Matsumoto, Kentaro Komori, Sosuke Ito, Yuta Michimura, and Yoichi Aso
  • Journal Title: Phys. Rev. A Volume: 94 Pages: 033822-033822
  • DOI: 10.1103/physreva.94.033822
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Estimation of losses in a 300 m filter cavity and quantum noise reduction in the KAGRA gravitational-wave detector (2016)
  • Author(s): Eleonora Capocasa, Matteo Barsuglia, Jerome Degallaix, Laurent Pinard, Nicolas Straniero, Roman Schnabel, Kentaro Somiya, Yoichi Aso, Daisuke Tatsumi, Raffaele Flaminio
  • Journal Title: Phys. Rev. D Volume: 93 Pages: 082004-082004
  • DOI: 10.1103/physrevd.93.082004
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] 5mg Suspended Mirror Driven by Measurement-Induced Backaction (2015)
  • Author(s): N. Matsumoto, K. Komori, Y. Michimura, G. Hayase, Y. Aso and K. Tsubono
  • Journal Title: Physical Review A Volume: 92 Pages: 033825-033825
  • DOI: 10.1103/physreva.92.033825
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] 低温鏡コーティング熱雑音の直接測定IV (2018)
  • Author(s): 谷岡諭，麻生洋一
  • Organizer: 日本物理学会 第73回年次大会
• [Presentation] 低温鏡コーティング熱雑音の直接測定III (2017)
  • Author(s): 谷岡諭，麻生洋一
  • Organizer: 日本物理学会 秋季大会
• [Presentation] 低温光共振器を用いたミラーコーティング熱雑音の直接測定 II (2017)
  • Author(s): 谷岡 諭, 麻生洋一
  • Organizer: 日本物理学会第72回年次大会
  • Place of Presentation: 大阪大学豊中キャンパス (大阪府, 吹田市)
• [Presentation] Status of The KAGRA Project (2017)
  • Author(s): Yoichi Aso on behalf of the KAGRA project
  • Organizer: LVC Meeting in Pasadena 2017
  • Place of Presentation: Hilton Pasadena, Pasadena, (USA)
  • Int'l Joint Research / Invited
• [Presentation] 低温光共振器を用いたミラーコーティング熱雑音の直接測定 (2016)
  • Author(s): 谷岡 諭, 麻生洋一
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 宮崎大学木花キャンパス(宮崎県, 宮崎市)
• [Presentation] R&D for the gravitational wave detector KAGRA (2016)
  • Author(s): Yoichi Aso for the KAGRA collaboration
  • Organizer: GR21
  • Place of Presentation: Columbia University, New York, (USA)
  • Int'l Joint Research