Nano-MRI using single spins in diamond

Nitrogen vacancy (NV) centers have been studied during the last years in different applications, ranging from life sciences to metrology. In our work, we use nano-scale nuclear magnetic resonance (nano-NMR) techniques with shallow NV centers to detect the signal produced by statistically polarized protons. Applying a magnetic field gradient allows us to target specific nuclear spins resulting in spectrally separated spin resonance frequencies. Under this condition, two spins at distant locations experience different magnetic fields, providing us with an increase in spatial resolution. We use a magnetic-coated AFM scanning probe to apply magnetic field gradients to a dense nuclear spin sample. This work paves the way for nano-NMR and other resonance techniques, such as nano-scale magnetic resonance imaging (nano-MRI).