[16a-F205-1~11] 11.4 Analog applications and their related technologies

[16a-F205-6] Analysis of characteristics of Al superconducting MKID resonators

〇Takashi Noguchi, Dominjon Agnes, Yutaro Sekimoto¹ (1.NAOJ)

Keywords:superconductor, microwave resonator, detector

The Q value and the variation of the resonance frequency of Al superconducting MKID resonators made of an Al film with respect to the temperature was fitted using an analytical approximation formula of the extended Mattis-Bardeen (M-B) equation. It was found that the variation of the resonance frequency shows almost the same temperature dependence in all the resonators, and it agrees well with the fitting using the approximate expression of the extended M-B equation. On the other hand, although the temperature dependence of the Q value is in good agreement with the fitting using the approximate expression of the extended MB equation, it was found that the saturation values of the Q value at low temperature largely depend on the magnitude of the imaginary part of the gap parameter.