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Yanis Abdedou

Publications and source records attributed to Yanis Abdedou.

2 recordsLinked to original sources

Methods for traceable scanning magnetometry using single nitrogen vacancy centers in diamond: determining orientation, distance and localization

Individual, scannable nitrogen vacancy (NV) centers in single crystal diamond nanostructures enable nanoscale, quantitative imaging of magnetic stray fields. Nevertheless, important parameters like distance between the NV center and the sample and the orientation of the NV high symmetry axis are often not known precisely and enter data evaluation as free fitting parameters. We here use scanning NV imaging on micro-patterned, perpendicularly magnetized stripes and discs. From these measurements, we directly infer NV - sample distance d_NV and the NV's azimuthal orientation without the need for an external vector magnet control. We determine d_NV = 31.5 nm, while we infer the azimuthal orientation with a precision of 3{\deg}. We additionally employ commercially available silicon needles to image the apex topography of our diamond nanostructures to detect surface contamination. Simultaneously, monitoring NV fluorescence as a function of the needle's position allows us to estimate the lateral placement of the NV inside the diamond nanostructure.

cond-mat.mes-hall

FRET between NV centers in diamond and chlorophyll molecules: a novel resource for multimodal sensing and imaging in plant cells

This work demonstrates efficient Forster resonance energy transfer (FRET) between ensembles of shallow nitrogen-vacancy (NV) centers located 7 nm and 9 nm below a single-crystal diamond surface and a naturally occurring fluorophore, namely a mixture of chlorophyll a and b molecules extracted from Arabidopsis thaliana. The broad fluorescence band of NV centers spectrally overlaps with the absorption of chlorophyll molecules, enabling FRET. As a result, depositing a chlorophyll layer on the diamond surface reduces the NV fluorescence lifetime from approximately 14 ns to below 4 ns, indicating efficient energy transfer. Laser-induced photobleaching of chlorophyll restores the unquenched NV lifetime. In contrast, NV centers located deeper within the diamond at depths of 40 nm and 72 nm remain unaffected, confirming that the observed quenching originates from a short-range FRET mechanism. The NV ensembles retain their optically detected magnetic resonance contrast while FRET is observed, demonstrating preservation of their spin properties. These proof-of-principle experiments establish the feasibility of combining FRET-based distance measurements with magnetic sensing using optically readable spins.

physics.bio-ph