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arXiv · 2309.12131

Temperature dependence of charge conversion during NV-center relaxometry

Isabel Cardoso Barbosa·Jonas Gutsche·Dennis Lönard·Stefan Dix·Artur Widera
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Abstract

Temperature-dependent nitrogen-vacancy (NV)-center relaxometry is an established tool to characterize paramagnetic molecules near to a sensing diamond, gaining momentum in different fields of science. However, recent results indicate that conversion between NV-center charge states impedes these measurements and influences the results for the $T_1$ time. While the temperature dependence of NV centers' $T_1$ time is well-studied, additional contributions from temperature-dependent charge conversion during the dark time may further affect the measurement results. We combine temperature-dependent relaxometry and fluorescence spectroscopy at varying laser powers to unravel the temperature dependence of charge conversion in nanodiamond for biologically relevant temperatures. While we observe a decrease of the $T_1$ time with increasing temperatures, charge conversion remains unaffected by the temperature change. These results allow the temperature dependent performance of $T_1$ relaxometry without further consideration of temperature dependence of charge conversion.

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Isabel Cardoso Barbosa, Jonas Gutsche, Dennis Lönard, Stefan Dix, Artur Widera. 2023-09-21. Temperature dependence of charge conversion during NV-center relaxometry. https://arxiv.org/abs/2309.12131

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