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arXiv · 2405.02021

A compact, portable device for microscopic magnetic imaging based on diamond quantum sensors

Alex Shaji·Kevin J. Rietwyk·Islay O. Robertson·Philipp Reineck·David A. Broadway·Jean-Philippe Tetienne
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Abstract

Magnetic imaging based on ensembles of diamond nitrogen-vacancy quantum sensors has emerged as a useful technique for the spatial characterisation of magnetic materials and current distributions. However, demonstrations have so far been restricted to laboratory-based experiments using relatively bulky apparatus and requiring manual handling of the diamond sensing element, hampering broader adoption of the technique. Here we present a simple, compact device that can be deployed outside a laboratory environment and enables robust, simplified operation. It relies on a specially designed sensor head that directly integrates the diamond sensor while incorporating a microwave antenna and all necessary optical components. This integrated sensor head is complemented by a small control unit and a laptop computer that displays the resulting magnetic image. We test the device by imaging a magnetic sample, demonstrating a spatial resolution of 4 $\mu$m over a field of view exceeding 1 mm, and a best sensitivity of 45 $\mu$T/$\sqrt{\rm Hz}$ per ($5\,\mu$m)$^2$ pixel. Our portable magnetic imaging instrument may find use in situations where taking the sample to be measured to a specialist lab is impractical or undesirable.

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Alex Shaji, Kevin J. Rietwyk, Islay O. Robertson, Philipp Reineck, David A. Broadway, Jean-Philippe Tetienne. 2024-05-03. A compact, portable device for microscopic magnetic imaging based on diamond quantum sensors. https://doi.org/10.1002/adsr.202400108

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