Development of superconducting infrared detector for cosmic background neutrino decay search

2017 Fiscal Year Final Research Report

• Project Area: Unification and Development of the Neutrino Science Frontier
• Project/Area Number: 25105007
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: University of Tsukuba
• Principal Investigator: KIM Shinhong 筑波大学, 数理物質系, 特命教授 (50161609)
• Co-Investigator(Kenkyū-buntansha): 武内 勇司 筑波大学, 数理物質系, 准教授 (00375403) ; 吉田 拓生 福井大学, 学術研究院工学系部門, 教授 (30220651)
• Co-Investigator(Renkei-kenkyūsha): IKEDA Hirokazu 宇宙航空研究開発機構, 宇宙科学研究所, 教授 (10132680)
• Research Collaborator: TAKEMASA Kenichi 筑波大学, 数理物質系, 研究員 (40817508) ; WAKASA Rena 筑波大学, 数理物質科学研究科, 大学院生 ; ASANO Chisa 筑波大学, 数理物質科学研究科, 大学院生 ; KASAHARA Kota 筑波大学, 数理物質科学研究科, 大学院生 ; KIUCHI Kenji 筑波大学, 数理物質科学研究科, 大学院生
• Project Period (FY): 2013-06-28 – 2018-03-31
• Keywords: 宇宙背景ニュートリノ / ニュートリノ質量 / 超伝導トンネル接合素子検出器 / 宇宙赤外線背景輻射 / 左右対称模型 / 極低温SOI増幅器 / ハフニウムSTJ

Outline of Final Research Achievements

In this research, we have developed the superconducting tunnel junction (STJ) detector for cosmic background neutrino decay search COBAND experiment. We required that the STJ detector should measure the energy of a single far-infrared photon with an energy around 25meV with an energy resolution of 2% for this COBAND experiment. To satisfy the requirement, we have developed a cryogenic preamplifier which can operate at 0.4K and be placed close to the STJ detector. We succeeded in amplifying the Nb/Al-STJ signal to a laser pulse light by a factor of 70 and improving the signal-to-noise ratio significantly.
We have also developed Hf-STJ with higher energy resolution than Nb/Al-STJ, and succeeded in observing the Hf-STJ signal to a laser pulse light by decreasing the leakage current significantly.

Free Research Field

素粒子実験