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arXiv · 1802.07402

Microwave device characterisation using a widefield diamond microscope

Andrew Horsley·Patrick Appel·Janik Wolters·Jocelyn Achard·Alexandre Tallaire·Patrick Maletinsky·Philipp Treutlein
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Abstract

Devices relying on microwave circuitry form a cornerstone of many classical and emerging quantum technologies. A capability to provide in-situ, noninvasive and direct imaging of the microwave fields above such devices would be a powerful tool for their function and failure analysis. In this work, we build on recent achievements in magnetometry using ensembles of nitrogen vacancy centres in diamond, to present a widefield microwave microscope with few-micron resolution over a millimeter-scale field of view, 130nT/sqrt-Hz microwave amplitude sensitivity, a dynamic range of 48 dB, and sub-ms temporal resolution. We use our microscope to image the microwave field a few microns above a range of microwave circuitry components, and to characterise a novel atom chip design. Our results open the way to high-throughput characterisation and debugging of complex, multi-component microwave devices, including real-time exploration of device operation.

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Andrew Horsley, Patrick Appel, Janik Wolters, Jocelyn Achard, Alexandre Tallaire, Patrick Maletinsky, Philipp Treutlein. 2018-02-21. Microwave device characterisation using a widefield diamond microscope. https://doi.org/10.1103/physrevapplied.10.044039

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