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arXiv · 1210.5574

Light narrowing of magnetic resonances in ensembles of nitrogen-vacancy centers in diamond

K. Jensen·V. M. Acosta·A. Jarmola·D. Budker
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Abstract

We investigate optically detected magnetic resonance signals from an ensemble of nitrogen-vacancy centers in diamond. The signals are measured for different light powers and microwave powers, and the contrast and linewidth of the magnetic-resonance signals are extracted. For a wide range of experimental settings of the microwave and light powers, the linewidth decreases with increasing light power, and more than a factor of two "light narrowing" is observed.Furthermore, we identify that spin-spin interaction between nitrogen-vacancy centers and substitutional nitrogen atoms in the diamond leads to changes in the lineshape and the linewidth of the optically detected magnetic-resonance signals. Finally, the importance of the light-narrowing effect for optimizing the sensitivity of magnetic field measurements is discussed.

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K. Jensen, V. M. Acosta, A. Jarmola, D. Budker. 2012-10-20. Light narrowing of magnetic resonances in ensembles of nitrogen-vacancy centers in diamond. https://doi.org/10.1103/physrevb.87.014115

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