Pump-Enhanced Continuous-Wave Magnetometry Using Nitrogen-Vacancy Ensembles
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2017-09-05 |
| Journal | Physical Review Applied |
| Authors | Sepehr Ahmadi, Haitham A. R. El-Ella, J. Bindslev Hansen, Alexander Huck, Ulrik L. Andersen |
| Institutions | Technical University of Denmark |
| Citations | 44 |
Abstract
Section titled āAbstractāEnsembles of nitrogen-vacancy centers in diamond are a highly promising\nplatform for high-sensitivity magnetometry, whose efficacy is often based on\nefficiently generating and monitoring magnetic-field dependent infrared\nfluorescence. Here we report on an increased sensing efficiency with the use of\na 532-nm resonant confocal cavity and a microwave resonator antenna for\nmeasuring the local magnetic noise density using the intrinsic nitrogen-vacancy\nconcentration of a chemical-vapor deposited single-crystal diamond. We measure\na near-shot-noise-limited magnetic noise floor of 200 pT/$\sqrt{\text{Hz}}$\nspanning a bandwidth up to 159 Hz, and an extracted sensitivity of\napproximately 3 nT/$\sqrt{\text{Hz}}$, with further enhancement limited by the\nnoise floor of the lock-in amplifier and the laser damage threshold of the\noptical components. Exploration of the microwave and optical pump-rate\nparameter space demonstrates a linewidth-narrowing regime reached by virtue of\nusing the optical cavity, allowing an enhanced sensitivity to be achieved,\ndespite an unoptimized collection efficiency of <2 %, and a low\nnitrogen-vacancy concentration of about 0.2 ppb.\n