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arXiv · 2604.15755

Optically detected magnetic resonance of nitrogen-vacancy centers in diamond using two-photon excitation

Lam T. Nguyen·Khanh Kieu
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Abstract

We demonstrate the use of two-photon excitation for observing the ground state optically detected magnetic resonance (ODMR) of nitrogen-vacancy centers in diamonds at room temperature. An ultrafast femtosecond laser at 1040 nm was used for excitation, while fluorescence signal read out was achieved through a combination of a PMT and a lock-in amplifier. The imaging capability of two-photon excitation fluorescence (2PEF) was utilized to map the distribution of NV centers in a bulk diamond and micro-sized diamonds. For the first time, ODMR traces of the nitrogen-vacancy center are observed with two-photon excitation, providing a promising tool for fast 3D quantum sensing and imaging.

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Lam T. Nguyen, Khanh Kieu. 2026-04-17. Optically detected magnetic resonance of nitrogen-vacancy centers in diamond using two-photon excitation. https://arxiv.org/abs/2604.15755

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