Broadband magnetometry by infrared-absorption detection of nitrogen-vacancy ensembles in diamond - Physics > Instrumentation and Detectors

Abstract: We demonstrate magnetometry by detection of the spin state of high-densitynitrogen-vacancy ensembles in diamond using optical absorption at 1042 nm. Withthis technique, measurement contrast, and collection efficiency can approachunity, leading to an increase in magnetic sensitivity compared to the morecommon method of collecting red fluorescence. Working at 75 K with a sensorwith effective volume $50 \times 50 \times 300$ microns^3, we project photonshot-noise limited sensitivity of 5 pT in one second of acquisition andbandwidth from dc to a few megahertz. Operation in a gradiometer configurationyields a noise floor of 7 nTrms at ~110 Hz in one second of acquisition.

Author: V. M. Acosta, E. Bauch, A. Jarmola, L. J. Zipp, M. P. Ledbetter, D. Budker

Source: https://arxiv.org/