Fiber-based scanning-probe magnetometry with nitrogen-vacancy spins in diamond nanobeams

Abstract

In modern-day research, magnetometry provides valuable information for a wide range of studies. Among all the different forms of magnetometers, the nitrogenvacancy (NV) lattice defect in diamond has emerged as a powerful magnetic field sensor thanks to the combination of sensitivity, spatial resolution and versatile capabilities. High-fidelity microwave control and optical readout of the NV spin over a wide range of conditions has enabled applications in condensed matter physics, chemistry, biology, geoscience and many more. In particular, its capability of visualizing magnetic phenomena with high spatial resolution has proven to be a powerful tool in both fundamental physics and applied sciences. Advances in NV magnetometry in the past decade have led to numerous breakthroughs, especially in revealing the nanoscale physics of condensed matter systems. However, the free-space optics generally used for optical interrogation of the NV spins are challenging to realize in cryogenic, intra-cellular, or other hard-to-reach environments. As such, realizing robust all-fiber-based NV probes with efficient optical readout could enable new measurements in low-temperature (quantum) or biological systems...