The properties of the nitrogen-vacancy center in milled chemical vapor deposition nanodiamonds
Year: 2026
Type: article
Abstract: Fluorescent nanodiamonds (FNDs) containing negatively charged nitrogen-vacancy (NV − ) centers are vital for many emerging quantum sensing applications from magnetometry to intracellular sensing in biology. However, developing a scalable fabrication method for FNDs hosting color centers with consistent bulk-like photoluminescence (PL) and spin coherence properties remains a highly desired but unrealized goal. Here, we investigate optimized ball milling of single-crystal diamonds produced via chemical vapor deposition (CVD) and containing 2 ppm of substitutional nitrogen and 0.3 ppm of NV − to achieve this goal. The NV charge state, PL lifetime, and spin properties of bulk CVD diamond samples are directly compared to milled CVD FNDs and commercial high-pressure high-temperature (HPHT) FNDs. We find that on average, the relative contribution of the NV − charge state to the total NV PL is lower and the NV PL lifetime is longer in CVD FNDs compared to HPHT FNDs, both likely due to the lower N s 0 concentration in CVD FNDs. The CVD bulk and CVD FNDs on average show similar average T 1 spin relaxation times of 3.2 ± 0.7 ms and 4.7 ± 1.6 ms, respectively, compared to 0.17 ± 0.01 ms for commercial HPHT FNDs. Our results demonstrate that ball milling of CVD diamonds enables the large-scale fabrication of NV ensembles in FNDs with bulk-like T 1 spin relaxation properties.
Source: Materials for Quantum Technology
Institutions: RMIT University, University of Stuttgart, National Institutes for Quantum Science and Technology, Tohoku University, Fraunhofer Institute for Applied Solid State Physics, The University of Melbourne, Center for Integrated Quantum Science and Technology, Princeton University, Princeton Plasma Physics Laboratory
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,695
Awards: Dopant engineering of diamond for quantum sensing technologies, G2195034164, G3627725911, Near-infrared quantum emitters in diamond: a new frontier in photonics, G4629353440, FOR 1493: Diamond Materials for Quantum Application, G8239160194, A nanodiamond voltage sensor: towards real-time, long-term neuronal sensing
OpenAlex ID: W7128674038