Nuclear magnetic resonance with a single NV scanning probe*

The single nitrogen vacancy (NV) probe has found extensive applications in performing scanning magnetometry to investigate various magnetic and electric phenomena. On the other hand, static diamond membranes or pillar arrays are typically used to conduct nanoscale nuclear magnetic resonance (NMR). While prior efforts have explored scanning the studied sample over a static diamond membrane, this configuration has limited practical uses. 

Our study showcases the possibility to utilize a scanning NV probe to perform nanoscale NMR measurements. Using dynamic decoupling, different nuclear signals on sample surfaces have been detected at a high signal to noise ratio. An NV-to-sample distance of 8 nm is determined, by fitting the magnetic fluctuations from ¹⁹F nuclear. In a proof-of-concept demonstration, we show the feasibility of studying nanoscale hydrophilicity and hydrophobicity by using a single NV probe. ¹H from water films on various sample surfaces have been measured. Notably, an increase in ¹H signals upon retracting the probe from a superhydrophobic surface is observed, which behaves distinctively compared to hydrophilic surfaces. 

Our results affirm the viability of using scanning NV probes for NMR type examinations of surfaces characteristics, which opens the door for the nanoscale NMR imaging in a wide variety of scientific domains via scanning NV.