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.
@article{arxiv.2206.08163,
title = {Magnetic imaging of superconducting qubit devices with scanning SQUID-on-tip},
author = {E. Marchiori and L. Ceccarelli and N. Rossi and G. Romagnoli and J. Herrmann and J. -C. Besse and S. Krinner and A. Wallraff and M. Poggio},
journal= {arXiv preprint arXiv:2206.08163},
year = {2022}
}