Sub-kelvin thermometer for on-chip measurements of microwave devices utilizing two-level systems in superconducting microresonators

Published

November 13, 2021

Author(s)

Jordan Wheeler, Michael Vissers, Maxime Malnou, Johannes Hubmayr, Joel Ullom, Jiansong Gao

Abstract

The design, implementation, and sensitivity of a new microwave multiplexable superconducting resonator thermometer based on two-level-systems are presented. The thermometer operates from 1 K to 50 mK and has the potential to measure down to 5 mK. The sensitivity measured in noise equivalent temperature is relatively uniform across the operational temperature range at 75 to 50 µK/√Hz. This thermometer, with a miniature footprint that requires no DC wiring, can be conveniently attached to the feedline of a cryogenic microwave device and measure its on-chip temperature. We demonstrate direct, fast (100s of Hz), and accurate temperature measurements of the transient and static chip heating of a kinetic inductance traveling-wave parametric amplifier induced by a strong pump tone. This thermometer may find broad applications in cryogenic microwave devices such as superconducting qubits and detectors.

Citation

Applied Physics Letters

Pub Type

Journals

Download Paper

https://doi.org/10.1063/5.0029351

Local Download

Keywords

Cryogenic thermometry, microwave resonators, superconducting resonators, microwave kinetic inductance detectors

Citation

Wheeler, J. , Vissers, M. , Malnou, M. , Hubmayr, J. , Ullom, J. and Gao, J. (2021), Sub-kelvin thermometer for on-chip measurements of microwave devices utilizing two-level systems in superconducting microresonators, Applied Physics Letters, [online], https://doi.org/10.1063/5.0029351, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=930710 (Accessed October 16, 2025)