Characterization of two-level system noise for microwave kinetic inductance detector comprising niobium film on silicon substrate

Abstract

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 $\mu$m, 4.00 $\mu$m) to (S, W) = (5.00 $\mu$m, 23.7 $\mu$m), and achieved an increased suppression of 5.5 dB in TLS noise.

arXiv comment14 pages, 12 figures

References in corpus (15)

• Study of loss in superconducting coplanar waveguide resonators
• Noise Properties of Superconducting Coplanar Waveguide Microwave Resonators
• Improving the Coherence Time of Superconducting Coplanar Resonators
• A semi-empirical model for two-level system noise in superconducting microresonators
• The NIKA2 large field-of-view millimeter continuum camera for the 30-m IRAM telescope
• A kilo-pixel imaging system for future space based far-infrared observatories using microwave kinetic inductance detectors
• Photon noise limited radiation detection with lens-antenna coupled Microwave Kinetic Inductance Detectors
• High optical efficiency and photon noise limited sensitivity of microwave kinetic inductance detectors using phase readout
• Multiplexed Readout for 1000-pixel Arrays of Microwave Kinetic Inductance Detectors
• Temperature Dependence of the Frequency and Noise of Superconducting Coplanar Waveguide Resonators
• Reduced frequency noise in superconducting resonators
• First light demonstration of the integrated superconducting spectrometer
• Suppression of radiation loss in high kinetic inductance superconducting co-planar waveguides
• Reactive magnetron sputter deposition of superconducting niobium titanium nitride thin films with different target sizes
• A forecast of the sensitivity on the measurement of the optical depth to reionization with the GroundBIRD experiment