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arXiv · 1505.02811

Relaxometry and dephasing imaging of superparamagnetic magnetite nanoparticles using a single qubit

Dominik Schmid-Lorch·Thomas Häberle·Friedemann Reinhard·Andrea Zappe·Michael Slota·Lapo Bogani·Amit Finkler·Jörg Wrachtrup
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Abstract

To study the magnetic dynamics of superparamagnetic nanoparticles we use scanning probe relaxometry and dephasing of the nitrogen-vacancy (NV) center in diamond, characterizing the spin-noise of a single 10-nm magnetite particle. Additionally, we show the anisotropy of the NV sensitivity's dependence on the applied decoherence measurement method. By comparing the change in relaxation (T 1 ) and dephasing (T 2 ) time in the NV center when scanning a nanoparticle over it, we are able to extract the nanoparticle's diameter and distance from the NV center using an Ornstein-Uhlenbeck model for the nanoparticle's fluctuations. This scanning-probe technique can be used in the future to characterize different spin label substitutes for both medical applications and basic magnetic nanoparticle behavior.

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Dominik Schmid-Lorch, Thomas Häberle, Friedemann Reinhard, Andrea Zappe, Michael Slota, Lapo Bogani, Amit Finkler, Jörg Wrachtrup. 2015-05-11. Relaxometry and dephasing imaging of superparamagnetic magnetite nanoparticles using a single qubit. https://doi.org/10.1021/acs.nanolett.5b00679

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