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arXiv · 2505.19207

Sensing single molecule magnets with nitrogen vacancy centers

Ariel Smooha·Jitender Kumar·Dan Yudilevich·John W. Rosenberg·Valentin Bayer·Rainer Stöhr·Andrej Denisenko·Tatyana Bendikov·Anna Kossoy·Iddo Pinkas·Hengxin Tan·Binghai Yan·Biprajit Sarjar·Joris van Slageren·Amit Finkler
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Abstract

Single-molecule magnets (SMMs) are molecules that can function as nanoscale magnets with potential use as magnetic memory bits. While SMMs can retain magnetization at low temperatures, characterizing them on surface and at room temperature remains challenging and requires specialized nanoscale techniques. Here, we use single nitrogen-vacancy (NV) centers in diamond as highly sensitive, broadband magnetic field sensors to detect the magnetic noise of cobalt-based SMMs deposited on a diamond surface. We measure the NV relaxation and decoherence times at 296 K and at 5-8 K, observing a significant influence of the SMMs on them. From this, we can infer the SMMs' magnetic noise spectral density (NSD) and underlying magnetic properties. Moreover, we observe the effect of an applied magnetic field on the SMMs' NSD at low temperatures. The method provides nanoscale sensitivity for characterizing SMMs under realistic conditions relevant to their use as surface-bound memory units.

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Ariel Smooha, Jitender Kumar, Dan Yudilevich, John W. Rosenberg, Valentin Bayer, Rainer Stöhr, Andrej Denisenko, Tatyana Bendikov, Anna Kossoy, Iddo Pinkas, Hengxin Tan, Binghai Yan, Biprajit Sarjar, Joris van Slageren, Amit Finkler. 2026-01-13. Sensing single molecule magnets with nitrogen vacancy centers. https://doi.org/10.1021/acs.nanolett.5c05066

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