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arXiv · 1003.3699

Ultra-sensitive Diamond Magnetometry Using Optimal Dynamic Decoupling

Liam T. Hall·Charles D. Hill·Jared H. Cole·Lloyd C. L. Hollenberg
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Abstract

New magnetometry techniques based on Nitrogen Vacancy (NV) defects in diamond have received much attention of late as a means to probe nanoscale magnetic environments. The sensitivity of a single NV magnetometer is primarily determined by the transverse spin relaxation time, $T_2$. Current approaches to improving the sensitivity employ crystals with a high NV density at the cost of spatial resolution, or extend $T_2$ via the manufacture of novel isotopically pure diamond crystals. We adopt a complementary approach, in which optimal dynamic decoupling techniques extend coherence times out to the self-correlation time of the spin bath. This suggests single spin, room temperature magnetometer sensitivities as low as 5\,pT\,Hz$^{-1/2}$ with current technology.

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Liam T. Hall, Charles D. Hill, Jared H. Cole, Lloyd C. L. Hollenberg. 2010-03-19. Ultra-sensitive Diamond Magnetometry Using Optimal Dynamic Decoupling. https://doi.org/10.1103/physrevb.82.045208

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