The 70th JSAP Spring Meeting 2023

Presentation information

Symposium (Oral)

Symposium » Latest trend of device technologies for quantum computing

[17p-A307-1~10] Latest trend of device technologies for quantum computing

Fri. Mar 17, 2023 1:30 PM - 5:00 PM A307 (Building No. 6)

Satoshi Iwamoto(Univ. of Tokyo), Kenichi Kawaguchi(Fujitsu Limited)

4:00 PM - 4:15 PM

[17p-A307-8] Microwave Characterization of Superconducting Ta Films Using Nb Buffer Layer

Yoshiro Urade1, Kay Yakushiji1, Manabu Tsujimoto1, Takahiro Yamada1, Kazumasa Makise1, Wataru Mizubayashi1, Kunihiro Inomata1 (1.AIST)

Keywords:superconducting qubit, tantalum, niobium

Ta is one of promising materials for low-loss electrodes of superconducting qubits. To obtain low-loss α-phase Ta films, we need to heat substrates up to several hundred degrees Celsius. At room temperature, β-phase Ta with larger loss grows. In this study, we use a Nb buffer layer to grow α-phase Ta films at room temperature and characterize their physical properties. Moreover, we fabricate planar microwave resonators made of the films and characterize them by microwave in a 10 mK environment.