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arXiv · 2411.05542

Quantum magnetometry of transient signals with a time resolution of 1.1 nanoseconds

Konstantin Herb·Laura A. Völker·John M. Abendroth·Nicholas Meinhardt·Laura van Schie·Pietro Gambardella·Christian L. Degen
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Abstract

Quantum magnetometers based on spin defects in solids enable sensitive imaging of various magnetic phenomena, such as ferro- and antiferromagnetism, superconductivity, and current-induced fields. Existing protocols primarily focus on static fields or narrow-band dynamical signals, and are optimized for high sensitivity rather than fast time resolution. Here, we report detection of fast signal transients, providing a perspective for investigating the rich dynamics of magnetic systems. We experimentally demonstrate our technique using a single nitrogen-vacancy (NV) center magnetometer at room temperature, reaching a best-effort time resolution of 1.1 ns, an instantaneous bandwidth of 0.9 GHz, and a time-of-flight precision better than 20 ps. The time resolution can be extended to the picosecond range by use of on-chip waveguides. At these speeds, NV quantum magnetometers will become competitive with time-resolved synchrotron X-ray techniques. Looking forward, adding fast temporal resolution to the spatial imaging capability further promotes single-spin probes as powerful research tools in spintronics, mesoscopic physics, and nanoscale device metrology.

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Konstantin Herb, Laura A. Völker, John M. Abendroth, Nicholas Meinhardt, Laura van Schie, Pietro Gambardella, Christian L. Degen. 2024-11-08. Quantum magnetometry of transient signals with a time resolution of 1.1 nanoseconds. https://doi.org/10.1038/s41467-025-55956-1

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