[20p-212B-1~14] 11.4 Analog applications and their related technologies

[20p-212B-1] Property of MKID resonators using a high quality Nb film (II)

〇Takashi Noguchi^1,2, Agnes Dominjon¹, Matthias Kroug¹, Satoru Mima², Chiko Otani² (1.NAOJ/NINS, 2.RIKEN)

Keywords:superconductor, microwave resonator, quality factor

A superconducting resonator was fabricated using a high quality Nb thin film having characteristics of residual resistance ratio RRR = 80 and superconducting transition temperature 9.4 K, and its resonance characteristics were investigated in detail.
The temperature dependence of the internal Q value and the resonance frequency of the high quality Nb thin film resonator can be explained very well by the theory considering contribution of quasiparticle resistance by phonon and electron-electron scattering in addition to Mattis-Bardeen theory and Kondo effect.