Stimulated Emission Depletion Microscopy Resolves Individual Nitrogen Vacancy Centers in Diamond Nanocrystals

Abstract

Nitrogen-vacancy (NV) color centers in nanodiamonds are highly promising for bioimaging and sensing. However, resolving individual NV centers within nanodiamond particles and the controlled addressing and readout of their spin state has remained a major challenge. Spatially stochastic superresolution techniques cannot provide this capability in principle, whereas coordinate-controlled super-resolution imaging methods, like stimulated emission depletion (STED) microscopy, have been predicted to fail in nanodiamonds.Here we show that, contrary to these predictions, STED can resolve single NV centers in 40À250 nm sized nanodiamonds with a resolution of ≈10 nm. Even multiple adjacent NVs located in single nanodiamonds can be imaged individually down to relative distances of ≈15 nm. Far-field optical super-resolution of NVs inside nanodiamonds is highly relevant for bioimaging applications of these fluorescent nanolabels. The targeted addressing and readout of individual NV À spins inside nanodiamonds by STED should also be of high significance for quantum sensing and information applications.

Subdiffraction optical manipulation of the charge state of nitrogen vacancy center in diamond

“…The lasers for charge-state conversion of CSD microscopy are much weaker than the lasers in STED microscopy with NV. 19,21 Furthermore, our experiments demonstrate that an optimized G laser duration would also improve the spatial resolution without changing the D laser duration(see Supplementary Information for details). Therefore, the durations of both the G laser and D laser should be carefully adjusted to improve the imaging quality.…”

“…With STED, the electron spin resonance signals of NV centers have been detected with a resolution lower than the diffraction limit. 12,21,22 A new super-resolution microscopy technique was recently developed by Han et al 15 The authors replaced the stimulated excitation of STED with the dark-state pumping of NV centers. The dark state was later proven to be the neutral charge NV center (NV 0 ) by other groups.…”

Diamond Nanophotonics

“…Some nanodiamonds contain more than a single NV center, and are often discarded for quantum applications. As reported by S ArroyoCamejo and colleagues [143] , individual NV centres were resolved within a single 100 nm nanodiamond with a resolution of ~ 30 nm. As exemplified in figure 11, individual NVs were isolated within a single nanodiamonds and their spin states could be resolved.…”

Superresolution optical magnetic imaging and spectroscopy using individual electronic spins in diamond

“…Coordinate-stochastic superresolution imaging methods, namely STochastic Optical Reconstruction Microscopy (STORM) and Photo Activated Localization Microscopy (PALM), readily offer high parallelization in sparse samples, but are prone to artefacts at high emitter densities and have been implemented until now only for a few NV centers per diffraction limited volume [12,13]. On the other hand, coordinate-deterministic superresolution methods provide targeted probing of individual NV spins with nanometric resolution [14][15][16], which is well suited for the purpose of coherent nanoscale AC magnetometry, where each NV acts as a local phase-controlled magnetometer probe.In this letter, we demonstrate the capability of spin-RESOLFT (REversible Saturable OpticaL Fluorescence Transitions), a coordinate-deterministic technique for combined far-field optical imaging and coherent spin manipulation, to map spatially varying magnetic fields at the nanoscale, including the NMR signal from external nuclear spins. Importantly, spin-RESOLFT does not require multi-wavelength excitation and high optical powers, as typically used with STimulated Emission Depletion (STED) [17] microscopy or Ground State Depletion (GSD) by metastable state pumping [18].…”