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arXiv · 1306.1594

Creating high density ensembles of nitrogen-vacancy centers in nitrogen-rich type Ib nanodiamonds

Long-Jyun Su·Chia-Yi Fang·Yu-Tang Chang·Kuan-Ming Chen·Yueh-Chung Yu·Jui-Hung Hsu·Huan-Cheng Chang
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Abstract

This work explores the possibility of increasing the density of negatively charged nitrogen-vacancy centers [NV-] in nanodiamonds using nitrogen-rich type Ib diamond powders as the starting materials. The nanodiamonds (10 - 100 nm in diameters) were prepared by ball-milling of microdiamonds, in which the density of neutral and automatically dispersed nitrogen atoms [N0] was measured by diffuse reflectance infrared Fourier transform spectroscopy (DRIFT). A systematic measurement for the fluorescence intensities and lifetimes of the crushed monocrystalline diamonds as a function of [N0] indicated that the [NV-] increases nearly linearly with [N0] at 100 - 200 ppm. The trend, however, failed to continue for nanodiamonds with higher [N0] (up to 390 ppm) but poorer crystallinity. We attribute the result to a combined effect of fluorescence quenching as well as the lower conversion efficiency of vacancies to NV- due to the presence of more impurities and defects in these as-grown diamond crystallites. The principles and practice of fabricating brighter and smaller fluorescent nanodiamonds (FNDs) are discussed.

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Long-Jyun Su, Chia-Yi Fang, Yu-Tang Chang, Kuan-Ming Chen, Yueh-Chung Yu, Jui-Hung Hsu, Huan-Cheng Chang. 2013-06-07. Creating high density ensembles of nitrogen-vacancy centers in nitrogen-rich type Ib nanodiamonds. https://arxiv.org/abs/1306.1594

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