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arXiv · 2411.10437

Nitrogen vacancy center in diamond-based Faraday magnetometer

Reza Kashtiban·Gavin W. Morley·Mark E. Newton·A T M Anishur Rahman
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Abstract

The nitrogen vacancy (NV) center in diamond is a versatile color center used for magnetometry, quantum computing, and quantum communications. In this article, using a single laser beam as a pump and probe, we measure the spin states of the NV center using the Faraday effect and use such measurements to develop a novel magnetic field sensor. Using the spin-state-dependent effect on the left and right circularly polarized light, we probe and confirm the existence of spin-orbit coupling in the NV center at room temperature. The sensitivity of our magnetometer is $350~$nT/$\sqrt{Hz}$, limited by the background produced by the laser trapped inside the diamond. We argue that by using an optical cavity and a high-purity diamond, sensitivities in the femtotesla level can be achieved.

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Reza Kashtiban, Gavin W. Morley, Mark E. Newton, A T M Anishur Rahman. 2024-11-15. Nitrogen vacancy center in diamond-based Faraday magnetometer. https://arxiv.org/abs/2411.10437

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