Study of stable optical cavity at low temperature

• Project/Area Number: 25287053
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: The University of Tokyo
• Principal Investigator: OHASHI MASATAKE 東京大学, 宇宙線研究所, 教授 (80213833)
• Co-Investigator(Kenkyū-buntansha): 山元 一広 東京大学, 宇宙線研究所, 助教 (00401290) ; 内山 隆 東京大学, 宇宙線研究所, 准教授 (60361656)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥17,160,000 (Direct Cost: ¥13,200,000、Indirect Cost: ¥3,960,000); Fiscal Year 2015: ¥5,980,000 (Direct Cost: ¥4,600,000、Indirect Cost: ¥1,380,000); Fiscal Year 2014: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000); Fiscal Year 2013: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000)
• Keywords: 重力波 / レーザー干渉計 / 極低温 / 光学薄膜

Outline of Final Research Achievements

The aim of this research is to realize a ultra-stable optical cavity at low temperrature. We measured the mechanical losses of optical thin films for high reflectivity mirror coating at low temperature (around 20K). We did not found any lowering of mechanical Q value at low temperature and the cooling of mirrors could reduce the thermal noise of mirros drastically. We confirmed that a long stable optical cavity at low temperature will be realized by using current techniques.

Research Products

• [Journal Article] Mechanical loss of a multilayer tantala/silica coating on a sapphire disk at cryogenic temperatures: Toward the KAGRA gravitational wave detector (2014)
  • Author(s): Eiichi Hirose, Kieran Craig, Hideki Ishitsuka, Iain W. Martin, Norikatsu Mio, Shigenori Moriwaki, Peter G. Murray, Masatake Ohashi, Sheila Rowan, Yusuke Sakakibara, Toshikazu Suzuki, Kouichi Waseda, Kyohei Watanabe, and Kazuhiro Yamamoto
  • Journal Title: Physical Review D Volume: 90 Issue: 10 Pages: 102004-102004
  • DOI: 10.1103/physrevd.90.102004
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Sapphire mirror for the KAGRA gravitational wave detector (2014)
  • Author(s): E. Hirose, D. Bajuk, G. Billingsley, T. Kajita, B. Kestner, N. Mio, M. Ohashi, B. Reichman, H. Yamamoto, and L. Zhang
  • Journal Title: Physical Review D Volume: 89 Issue: 6 Pages: 062003-062003
  • DOI: 10.1103/physrevd.89.062003
  • Peer Reviewed / Open Access
• [Presentation] KAGRA低温系の現状II (2016)
  • Author(s): 山元一広, Kieran Craig, 梶田隆章, 宮本昂拓, 田中宏樹, 萩原綾子, 木村誠宏, Rahul Kumar, 鈴木敏一, 都丸隆行, KAGRA Cryogenics Subgroup
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 宮崎大学（宮崎県宮崎市）
  • Year and Date: 2016-09-22
• [Presentation] Cryogenic Payload Issues (2015)
  • Author(s): Kazuhiro Yamamoto
  • Organizer: ELiTES: 4th general meeting
  • Place of Presentation: Tokyo Institute of Technology
  • Year and Date: 2015-12-02
  • Int'l Joint Research / Invited
• [Presentation] Measurement of coating mechanical loss (2015)
  • Author(s): J. Katayama, K. Craig, K. Yamamoto and M. Ohashi
  • Organizer: ELiTES: 4th general meeting
  • Place of Presentation: Tokyo Institute of Technology
  • Year and Date: 2015-12-02
  • Int'l Joint Research
• [Presentation] KAGRA 用低温懸架装置の開発VI (2015)
  • Author(s): 山元一広，A. Khalaidovski，宮本昂拓，榊原裕介，田中宏樹，内山隆，阿久津智忠，萩原綾子，木村誠宏，R. Kumar，久米達哉，小池重明，村上巌，鈴木敏一，寺嶋眞一，都丸隆行，豊田惠嗣，陳たん，R. DeSalvo，E. Majorana
  • Organizer: 日本物理学会第70回年次大会
  • Place of Presentation: 早稲田大学(東京都新宿区)
  • Year and Date: 2015-03-22
• [Presentation] The ELiTES Collaboration, Japanese viewpoint (2015)
  • Author(s): 山元一広
  • Organizer: ELiTES: 3rd general meeting
  • Place of Presentation: 駐日欧州連合代表部（東京都港区）
  • Year and Date: 2015-02-09
• [Presentation] KAGRA 用低温懸架装置の開発 V (2014)
  • Author(s): 山元一広，高橋竜太郎，田中宏樹，宮本昂拓，小野謙次，関口貴令，榊原裕介，上泉眞裕，廣瀬榮一，A. Khalaidovski，R.Kumar，内山隆，三代木伸二，阿久津智忠，石崎秀晴，鈴木敏一，麻生洋一，宗宮健太郎
  • Organizer: 日本物理学会2014年秋季大会
  • Place of Presentation: 佐賀大学（佐賀県佐賀市）
  • Year and Date: 2014-09-20
• [Presentation] KAGRA重力波検出器の低温鏡系の開発 (2014)
  • Author(s): 廣瀬榮一，GariLynn Billingsley，梶田隆章，三尾典克，大橋正建，山本博章A，Liyuan Zhang
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 東海大学湘南キャンパス（神奈川県平塚市）
  • Year and Date: 2014-03-27
• [Presentation] KAGRA用低温懸架装置の開発IV (2014)
  • Author(s): 山元一広，高橋竜太郎，小野謙次，関口貴令，榊原裕介，東谷千比呂，上泉眞裕，岩崎詩子，廣瀬榮一，A. Khalaidovski，R. Kumar，内山隆，三代木伸二，大橋正健，阿久津智忠，石崎秀晴，鈴木敏一，木村誠宏，小池重明，坪野公夫，麻生洋一，牛場崇文，柴田和憲，陳タン，大前宣昭，宗宮健太郎他
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 東海大学湘南キャンパス（神奈川県平塚市）
  • Year and Date: 2014-03-27
• [Presentation] Overview of KAGRA cryogenic payload development (2013)
  • Author(s): 山元一広
  • Organizer: ELiTES: ２ｎd general meeting
  • Place of Presentation: 駐日欧州連合代表部（東京都港区）
  • Year and Date: 2013-12-04
• [Remarks] 東京大学宇宙線研究所KAGRAホームページ
  • URL: http://gwcenter.icrr.u-tokyo.ac.jp/
• [Remarks] KAGRAホームページ
  • URL: http://gwcenter.icrr.u-tokyo.ac.jp/