AIP conference proceedings

Improving the quality factor of superconducting resonators by post-process surface treatment

Daria A. Kalacheva, Gleb Fedorov, Anastasia A. Kulakova, Julia Zotova, Evgeny V. Korostylev, Ivan Khrapach, Alexey Vladimirovich Ustinov, O. V. Astafiev

Published Jan 1, 2020• 6 citations

Publisher

Abstract

We present a specific method for fabrication of the original evaporation mask and characterisation of the superconduct- ing coplanar waveguide (CPW) resonators based on the shadow evaporation technique [1]. We show that silicon dioxide can be successfully removed by etching process in HF-based solutions. This treatment significantly increases the intrinsic quality factor Qi of the resonators and is also suitable for other superconducting structures operated at temperatures of the order of 20 mK. In this report we present a design of superconducting CPW resonators with a high quality factor to study fundamental problems of high kinetic inductance of aluminum ultra-thin films. Our kinetic inductance research was motivated by the necessity of ultra-short and high quality resonators which could be suitable for qubit systems. Also this kinetic inductance could be used in the development of parametric amplifiers [2] or new types of qubits based on quantum phase slip [3].

DOI: 10.1063/5.0011900

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