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Flux-tunable heat sink for quantum electric circuits



Matti Partanen, K-Y Tan, S Masuda, Joonas Govenius, Russell Lake, Mate Jenei, Leif Gronberg, Juha Hassel, S Simbierowicz, Visa Vesterinen, J Tuorila, T Ala-Nissila, Mikko Mottonen


Superconducting microwave circuits show great potential for practical quantum technological applications such as quantum information processing. However, fast and on-demand initialization of the quantum degrees of freedom in these devices remains a challenge. Here, we experimentally implement a tunable heat sink that is potentially suitable for the initialization of superconducting qubits. Our device consists of two coupled resonators. The first resonator has a high quality factor and a fixed frequency whereas the second resonator is designed to have a low quality factor and a tunable resonance frequency. We engineer the low quality factor using an on-chip resistor and the frequency tunability using a superconducting quantum interference device. When the two resonators are in resonance, the photons in the high-quality resonator can be efficiently dissipated. We show that the corresponding loaded quality factor can be tuned from above 105 down to a few thousand at 10 GHz in good quantitative agreement with our theoretical model.
Nature - Scientific Reports


quantum technological applications, microwave circuits, quantum technology, superconducting, high quality factor, fixed frequency, low quality factor, tunable resonance frequency, on-chip resistor, superconducting quantum interference device, photons


Partanen, M. , Tan, K. , Masuda, S. , Govenius, J. , Lake, R. , Jenei, M. , Gronberg, L. , Hassel, J. , Simbierowicz, S. , Vesterinen, V. , Tuorila, J. , Ala-Nissila, T. and Mottonen, M. (2018), Flux-tunable heat sink for quantum electric circuits, Nature - Scientific Reports, [online],, (Accessed June 14, 2024)


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Created April 19, 2018, Updated October 12, 2021