Multimodal Super-Resolution Imaging of Nitrogen-Vacancy Centers via High-Index-Induced Structured Illumination Microscopy and Optically Detected Magnetic Resonance Spectrometry.

Structured illumination microscopy (SIM) allows for optical imaging with spatial resolution that surpasses the diffraction limit. To further enhance this super-resolution capability, we present a multimodal approach that integrates SIM with optically detected magnetic resonance (ODMR) of nitrogen-vacancy (NV) centers in diamond-a platform considered one of the most promising platforms for quantum sensing and computing. Both theoretical modeling and experimental results reveal that diamond's high refractive index supports finer structured illumination patterns, thereby accessing higher spatial frequencies and yielding improved resolution. This combined strategy not only enhances NV center localization precision and achieves sub-100-nm resolution but also facilitates spin coherence analysis. Leveraging the high refractive index of diamond in SIM thus offers a powerful pathway toward advancing quantum applications at the nanoscale.