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DOE OSTI · 1994325

Effects of laser-annealing on fixed-frequency superconducting qubits

Kim, Hyunseong·Jünger, Christian·Morvan, Alexis·Barnard, Edward S.·Livingston, William P.·Altoé, M. P.·Kim, Yosep·Song, Chengyu·Chen, Larry·Kreikebaum, John Mark·Ogletree, D. Frank·Santiago, David I.·Siddiqi, Irfan
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Abstract

As superconducting quantum processors increase in complexity, techniques to overcome constraints on frequency crowding are needed. The recently developed method of laser-annealing provides an effective post-fabrication method to adjust the frequency of superconducting qubits. In this work, we present an automated laser-annealing apparatus based on conventional microscopy components and demonstrate preservation of highly coherent transmons. In addition, we perform noise spectroscopy to investigate the change in defect features, in particular, two-level system defects, after laser-annealing. Finally, we present a local heating model as well as demonstrate aging stability for laser-annealing on the wafer scale. Our work constitutes an important step toward both understanding the underlying physical mechanism and scaling up laser-annealing of superconducting qubits.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYJosephson effectJosephson qubit measurement systemannealingelectron energy loss spectroscopyquantum computingspectroscopystark effectsuperconducting devicessuperconducting quantum computingtransmission electron microscopy

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Kim, Hyunseong, Jünger, Christian, Morvan, Alexis, Barnard, Edward S., Livingston, William P., Altoé, M. P., Kim, Yosep, Song, Chengyu, Chen, Larry, Kreikebaum, John Mark, Ogletree, D. Frank, Santiago, David I., Siddiqi, Irfan. 2022-10-05. Effects of laser-annealing on fixed-frequency superconducting qubits. https://doi.org/10.1063/5.0102092

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