2021/10/31 by Yoshinori Sueno, Shunsuke Honda, S. Honda +10
Physics and Astronomy · #Condensed matter physics #Detector #Electric field #Inductance #Kinetic inductance #Materials science #Microwave #Niobium #Noise (video) #Noise-equivalent power #Nuclear magnetic resonance #Optics #Optoelectronics #Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Resonator #Silicon #Substrate (aquarium) #Superconducting and THz Device Technology #Voltage #physics.ins-det
paper · pdf · doi:10.1093/ptep/ptac023
published as Prog Theor Exp Phys (2022) · 14 pages, 12 figures
arxiv created 2022/01/27 · openalex publication_date 2022/01/31 · arxiv updated 2022/03/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
A microwave kinetic inductance detector (MKID) is a cutting-edge superconducting detector. It comprises a resonator circuit constructed with a superconducting film on a dielectric substrate. To expand its field of application, it is important to establish a method to suppress the two-level system (TLS) noise that is caused by the electric fluctuations between the two energy states at the surface of the substrate. The electric field density can be decreased by expanding the strip width (S) and gap width from the ground plane (W) in the MKID circuit, allowing the suppression of TLS noise. However, this effect has not yet been confirmed for MKIDs made with niobium films on silicon substrates. In this study, we demonstrate its effectiveness for such MKIDs. We expanded the dimension of the circuit from (S, W) = (3.00 μm, 4.00 μm) to (S, W) = (5.00 μm, 23.7 μm), and achieved an increased suppression of 5.5 dB in TLS noise.