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arXiv · 2312.05892

Quasiparticle dynamics in a superconducting qubit irradiated by a localized infrared source

Rodrigo Benevides·Maxwell Drimmer·Giacomo Bisson·Francesco Adinolfi·Uwe von Lüpke·Hugo Michiel Doeleman·Gianluigi Catelani·Yiwen Chu
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Abstract

A known source of decoherence in superconducting qubits is the presence of broken Cooper pairs, or quasiparticles. These can be generated by high-energy radiation, either present in the environment or purposefully introduced, as in the case of some hybrid quantum devices. Here, we systematically study the properties of a transmon qubit under illumination by focused infrared radiation with various powers, durations, and spatial locations. Despite the high energy of incident photons, our observations agree well with a model of low-energy quasiparticle dynamics dominated by trapping. This technique can be used for understanding and potentially mitigating the effects of high-energy radiation on superconducting circuits with a variety of geometries and materials.

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Rodrigo Benevides, Maxwell Drimmer, Giacomo Bisson, Francesco Adinolfi, Uwe von Lüpke, Hugo Michiel Doeleman, Gianluigi Catelani, Yiwen Chu. 2023-12-10. Quasiparticle dynamics in a superconducting qubit irradiated by a localized infrared source. https://doi.org/10.1103/physrevlett.133.060602

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