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arXiv · 1701.06838

Level anti-crossing magnetometry with color centers in diamond

Huijie Zheng·Georgios Chatzidrosos·Arne Wickenbrock·Lykourgos Bougas·Reinis Lazda·Andris Berzins·Florian Helmuth Gahbauer·Marcis Auzinsh·Ruvin Ferber·Dmitry Budker
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Abstract

Recent developments in magnetic field sensing with negatively charged nitrogen-vacancy centers (NV) in diamond employ magnetic-field (MF) dependent features in the photoluminescence (PL) and eliminate the need for microwaves (MW). Here, we study two approaches towards improving the magnetometric sensitivity using the ground-state level anti-crossing (GSLAC) feature of the NV center at a background MF of 102.4\,mT. Following the first approach, we investigate the feature parameters for precise alignment in a dilute diamond sample; the second approach extends the sensing protocol into absorption via detection of the GSLAC in the diamond transmission of a 1042\,nm laser beam. This leads to an increase of GSLAC contrast and results in a magnetometer with a sensitivity of 0.45\,nT/$\sqrt{\text{Hz}}$ and a photon shot-noise limited sensitivity of 12.2 pT/$\sqrt{\rm{Hz}}$.

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Huijie Zheng, Georgios Chatzidrosos, Arne Wickenbrock, Lykourgos Bougas, Reinis Lazda, Andris Berzins, Florian Helmuth Gahbauer, Marcis Auzinsh, Ruvin Ferber, Dmitry Budker. 2017-01-24. Level anti-crossing magnetometry with color centers in diamond. https://arxiv.org/abs/1701.06838

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