Colloquium: "Nanoscale Quantum Sensing With Point Defects in Diamond"

Nov 8, 2023, 4:00 pm5:15 pm
General Public (virtual)



Event Description

The nitrogen vacancy (NV) center in diamond exhibits spin-dependent fluorescence and long spin coherence times under ambient conditions, enabling applications in quantum materials and devices. NV centers near the surface can have strong interactions with external materials and spins, enabling new forms of nanoscale spectroscopy. However, NV spin coherence degrades within 100 nanometers of the surface, suggesting that diamond surfaces are plagued with ubiquitous defects. I will describe our recent efforts to correlate direct materials characterization with single spin measurements to devise methods to stabilize highly coherent NV centers within nanometers of the surface [1]. We deploy these coherent shallow NV centers for a new nanoscale sensing technique, whereby we use covariance measurements of two or more NV centers to measure two-point magnetic field correlators [2]. Furthermore, we have developed new methods to couple target molecules to NV centers using a versatile strategy to directly functionalize C–H bonds on single-crystal diamond surfaces under ambient conditions using visible light. Our approach to surface functionalization based on visible light-driven C–H bond activation opens the door to deploying NV centers as a broad tool for chemical sensing and single molecule spectroscopy.

Peter Dugan