Quantum Sensing and Imaging of Spin Transport and Dynamics in Quantum Materials

Exploring new class of quantum materials with advanced magnetic and electronic properties has been a central focus of modern condensed matter physics over the past decades. The success of these efforts relies simultaneously on advances in theory, material synthesis, and development of new, sensitive metrology tools to characterize the key material properties at the nanoscale. Nitrogen-vacancy (NV) centers, optically active atomic spin defects in diamond, are naturally relevant in this context due to excellent quantum coherence, unprecedented spatial and field sensitivity, and remarkable functionality over broad experimental conditions. Serving as a local probe of multiple degrees of freedom, NV centers are ideally posed to investigate the fundamental correlations between microscopic magnetic textures and the underlying charge, spin, and thermal transport properties of quantum materials. In this talk, I will present our recent work on using NV centers to perform quantum sensing of emergent quantum materials. Specifically, we have utilized NV centers to visualize the exotic spin properties of topological magnetic materials [1-2] and antiferromagnetic insulators [3], revealing the fundamental physics underlying nanoscale spin transport and dynamic behaviors. Taking advantage of NV-magnon based hybrid systems, we also achieved electrical control of coherent NV spin rotations, promoting the role of NV centers at the forefront research of quantum technologies [4]. Lastly, I will briefly discuss our ongoing efforts to explore 2D quantum sensing technologies using emergent color centers beyond NVs [5].