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arXiv · 2206.08163

Magnetic imaging of superconducting qubit devices with scanning SQUID-on-tip

E. Marchiori·L. Ceccarelli·N. Rossi·G. Romagnoli·J. Herrmann·J. -C. Besse·S. Krinner·A. Wallraff·M. Poggio
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Abstract

We use a scanning superconducting quantum interference device (SQUID) to image the magnetic flux produced by a superconducting device designed for quantum computing. The nanometer-scale SQUID-on-tip probe reveals the flow of superconducting current through the circuit as well as the locations of trapped magnetic flux. In particular, maps of current flowing out of a flux-control line in the vicinity of a qubit show how these elements are coupled, providing insight on how to optimize qubit control.

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E. Marchiori, L. Ceccarelli, N. Rossi, G. Romagnoli, J. Herrmann, J. -C. Besse, S. Krinner, A. Wallraff, M. Poggio. 2022-06-16. Magnetic imaging of superconducting qubit devices with scanning SQUID-on-tip. https://doi.org/10.1063/5.0103597

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