In situ frequency tuning of superconducting resonators via nonlinear kinetic inductance

Published

March 23, 2026

Author(s)

Michael Vissers, Jordan Wheeler, Paul Szypryt, Andrea Giachero, Jason Austermann, Johannes Hubmayr, Galen O'Neil, Joel Ullom, Jiansong Gao

Abstract

Superconducting microresonators have diverse applications, including microwave kinetic inductance detectors, microwave superconducting quantum interference device multiplexers, and qubits. Arrays of such devices are typically addressed using microwave frequency combs with probe tones matched to individual device resonances, however, resonator frequency collisions caused by wafer non-uniformity and fabrication variations significantly limit usable device yields. In this letter, we present a novel technique that mitigates these frequency collisions without the need for ex post facto processing. By leveraging nonlinear kinetic inductance and persistent current in a superconducting loop, we achieve in situ tuning of individual resonator frequencies within an array during device cooldown, effectively resolving frequency collisions in a way that is both highly flexible and reversible. We successfully demonstrate this technique by tuning a small array of 4 resonators to both identical frequencies and a uniformly spaced frequency comb. This in situ resonator tuning approach provides a universal solution for improving yield and multiplexing density in large resonator arrays, addressing a critical need for scaling up superconducting detector and qubit systems.

Citation

Applied Physics Letters

Volume

128

Pub Type

Journals

Download Paper

https://doi.org/10.1063/5.0316371

Local Download

Keywords

tunable superconducting nonlinear kinetic inductance NbTiN microwave resonator

Citation

Vissers, M. , Wheeler, J. , Szypryt, P. , Giachero, A. , Austermann, J. , Hubmayr, J. , O'Neil, G. , Ullom, J. and Gao, J. (2026), In situ frequency tuning of superconducting resonators via nonlinear kinetic inductance, Applied Physics Letters, [online], https://doi.org/10.1063/5.0316371, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=960604 (Accessed July 22, 2026)

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