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تسجيل مستخدم جديدBroadband magnetometry by infrared-absorption detection of nitrogen-vacancy ensembles in diamond
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We demonstrate magnetometry by detection of the spin state of high-density nitrogen-vacancy ensembles in diamond using optical absorption at 1042 nm. With this technique, measurement contrast, and collection efficiency can approach unity, leading to an increase in magnetic sensitivity compared to the more common method of collecting red fluorescence. Working at 75 K with a sensor with effective volume $50 times 50 times 300$ microns^3, we project photon shot-noise limited sensitivity of 5 pT in one second of acquisition and bandwidth from dc to a few megahertz. Operation in a gradiometer configuration yields a noise floor of 7 nTrms at ~110 Hz in one second of acquisition.
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Quantum sensors based on optically active defects in diamond such as the nitrogen vacancy (NV) centre represent a promising platform for nanoscale sensing and imaging of magnetic, electric, temperature and strain fields. Enhancing the optical interfa
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We present systematic measurements of longitudinal relaxation rates ($1/T_1$) of spin polarization in the ground state of the nitrogen-vacancy (NV$^-$) color center in synthetic diamond as a function of NV$^-$ concentration and magnetic field $B$. NV
$^-$ centers were created by irradiating a Type 1b single-crystal diamond along the [100] axis with 200 keV electrons from a transmission electron microscope with varying doses to achieve spots of different NV$^-$ center concentrations. Values of ($1/T_1$) were measured for each spot as a function of $B$.
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