4 research outputs found
Shallow Silicon Vacancy Centers with lifetime-limited optical linewidths in Diamond Nanostructures
The negatively charged silicon vacancy center (SiV) in diamond is a
promising, yet underexplored candidate for single-spin quantum sensing at
sub-kelvin temperatures and tesla-range magnetic fields. A key ingredient for
such applications is the ability to perform all-optical, coherent addressing of
the electronic spin of near-surface SiV centers. We present a robust and
scalable approach for creating individual, 50nm deep SiV with
lifetime-limited optical linewidths in diamond nanopillars through an
easy-to-realize and persistent optical charge-stabilization scheme. The latter
is based on single, prolonged 445nm laser illumination that enables continuous
photoluminescence excitation spectroscopy, without the need for any further
charge stabilization or repumping. Our results constitute a key step towards
the use of near-surface, optically coherent SiV for sensing under extreme
conditions, and offer a powerful approach for stabilizing the
charge-environment of diamond color centers for quantum technology
applications.Comment: 15 pages, 13 figures including supplementary informatio
Temperature Dependent Photophysics of Single NV Centers in Diamond
We present a comprehensive study of the temperature and magnetic-field
dependent photoluminescence (PL) of individual NV centers in diamond, spanning
the temperature-range from cryogenic to ambient conditions. We directly observe
the emergence of the NV's room-temperature effective excited state structure
and provide a clear explanation for a previously poorly understood broad
quenching of NV PL at intermediate temperatures around 50 K. We develop a model
that quantitatively explains all of our findings, including the strong impact
that strain has on the temperaturedependence of the NV's PL. These results
complete our understanding of orbital averaging in the NV excited state and
have significant implications for the fundamental understanding of the NV
center and its applications in quantum sensing.Comment: 5 pages, 4 figures plus Supplementary Material. Questions and
comments are welcome. arXiv admin note: text overlap with arXiv:2105.0807
Low temperature photo-physics of single NV centers in diamond
International audienceWe investigate the magnetic field dependent photo-physics of individual Nitrogen-Vacancy (NV) color centers in diamond under cryogenic conditions. At distinct magnetic fields, we observe significant reductions in the NV photoluminescence rate, which indicate a marked decrease in the optical readout efficiency of the NV's ground state spin. We assign these dips to excited state level anti-crossings, which occur at magnetic fields that strongly depend on the effective, local strain environment of the NV center. Our results offer new insights into the structure of the NVs' excited states and a new tool for their effective characterization. Using this tool, we observe strong indications for strain-dependent variations of the NV's orbital g-factor, obtain new insights into NV charge state dynamics, and draw important conclusions regarding the applicability of NV centers for low-temperature quantum sensing