Microwave device characterisation using a widefield diamond microscope

TL;DR

This paper introduces a widefield diamond-based microwave microscope capable of noninvasive, high-resolution imaging of microwave fields for device analysis and debugging, advancing quantum and classical microwave technology diagnostics.

Contribution

The work presents a novel widefield microwave microscope with micron-scale resolution and high sensitivity, enabling in-situ imaging and characterization of microwave devices.

Findings

Achieved micron-scale resolution imaging of microwave fields.

Demonstrated imaging of various microwave circuitry components.

Characterized a new atom chip design using the microscope.

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.