Design and Fabrication of Microwave Kinetic Inductance Detectors using NbN Symmetric Spiral Resonator Array

11th European Conference on Applied Superconductivity

Hayashi, K.^1 ; Saito, A.^1 ; Ogawa, Y.^1 ; Murata, M.^1 ; Sawada, T.^1 ; Nakajima, K.^1 ; Yamada, H.^1 ; Ariyoshi, S.^2 ; Taino, T.^3 ; Tanoue, H.^3 ; Otani, C.^4 ; Ohshima, S.^1

Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa, Japan^1

Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Japan^2

Graduate School of Science and Engineering, Saitama University, 255 Okubo, Sakura-ku, Saitama, Japan^3

RIKEN Advanced Science Institute Terahertz Sensing and Imaging Team, 2-1 Hirosawa, Wako, Japan^4

关键词: Broadband terahertz;    Dc magnetron sputtering;    Dielectric substrates;    Kinetic inductance detectors;    Sapphire substrates;    Spiral resonators;    Spiral structures;    Unloaded quality factors;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/4/042015/pdf
DOI  :  10.1088/1742-6596/507/4/042015

来源: IOP

【 摘 要 】

We designed and fabricated a microwave kinetic inductance detector (MKID) using a niobium nitride (NbN) symmetric spiral resonator array. Previously we revealed that a rewound spiral structure works as not only a high-Q half-wavelength resonator but also as a broadband terahertz antenna. We conducted simulations for a 9 resonator array assuming NbN as the superconducting material and sapphire as the dielectric substrate, and obtained a maximum attenuation of over 30 dB and unloaded quality factors of over 2×105for frequencies between 4.4 and 4.9 GHz. We fabricated the 9 resonator array MKID using NbN thin film deposited on an m-sapphire substrate by using dc magnetron sputtering. We observed half-wavelength resonances of around 4.5 GHz at 4 K. We measured the optical response of the MKID. The frequency shift was 0.5 MHz when illuminated with 650 nm photons.