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arXiv · 2509.06500

Tuning of SiV quantum emission in nitrogen-doped nanodiamonds by dual-color excitation

A. A. Zhivopistsev·A. M. Romshin·A. V. Gritsienko·D. G. Pasternak·R. K. Bagramov·V. P. Filonenko·F. M. Maksimov·A. I. Chernov·A. M. Skomorokhov·N. I. Kargin·I. I. Vlasov
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Abstract

The charge dynamics of silicon-vacancy (SiV) centers have been investigated for the first time in high-pressure high-temperature nanodiamonds (NDs) with varying concentrations of substitutional nitrogen (Ns). We demonstrate a controlled sixfold enhancement of SiV- photoluminescence (PL) under dual-color excitation, consisting of strong red (~660 nm) illumination combined with weak green (~530 nm) excitation. The measured dependencies of SiV- PL lifetime and intensity on excitation wavelength, together with the enhancement dependence on Ns concentration in the studied nanodiamonds, provide unambiguous evidence of the involvement of donor nitrogen in SiV-emission dynamics. Saturation curves and second-order PL intensity correlation measurements further indicate suppression of the population of the optically inactive SiV2- state upon the addition of green excitation. These results unlock a practical pathway toward engineering optically-controlled and scalable quantum emitters based on SiV-luminescent diamond nanoparticles.

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A. A. Zhivopistsev, A. M. Romshin, A. V. Gritsienko, D. G. Pasternak, R. K. Bagramov, V. P. Filonenko, F. M. Maksimov, A. I. Chernov, A. M. Skomorokhov, N. I. Kargin, I. I. Vlasov. 2025-09-08. Tuning of SiV quantum emission in nitrogen-doped nanodiamonds by dual-color excitation. https://arxiv.org/abs/2509.06500

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