Development of Terahertz Photon Counting Technology for Astronomical Observation

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K13469
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: Ezawa Hajime 国立天文台, チリ観測所, 助教 (60321585)
• Co-Investigator(Kenkyū-buntansha): 松尾 宏 国立天文台, 先端技術センター, 准教授 (90192749) ; 浮辺 雅宏 国立研究開発法人産業技術総合研究所, エレクトロニクス・製造領域, 研究グループ長 (00344226)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 電波天文学 / テラヘルツ波天文観測 / 光子計数技術

Outline of Final Research Achievements

Various key technologies to realize the terahertz photon counting detectors for astronomical observation are studied and developed. We decided to integrate a superconducting tunneling junction (SIS junction) into a photon counting detector. For this we developed a superconducting tunnel junction (SIS) with low leakage current at CRAVITY facility in AIST, and successfully realized a junction with leakage current as low as 1 pA. Based on this achievement we designed an SIS detector with a twin-slot antenna and a choke filter, and evaluated the performance by numerical simulations. The design of the readout circuit is also studied, which includes the first stage FET mounted next to the SIS detector. In order to cool these devices, we also developed a helium-4 sorption cooler, which has relatively high cooling power. These achievements will play important roll to realize the photon counting detectors for terahertz astronomy.

Free Research Field

宇宙物理学