Quantum Lab Tour

Color centers in diamond, particularly the ones formed by the negatively-charged nitrogen-vacancy (NV) pairs below, have emerged as a versatile quantum system for sensitive physical metrology, magnetometry and chemical detection. They are sensitive to magnetic field fluctuations and can be used as a quantum sensor to acquire nuclear magnetic resonance (NMR) spectroscopy from interfaces with optical resolution or better. To date, quantum sensing approaches have seen little application in the Earth sciences although, as shown by a recent Workshop Report on Quantum Information Science and Technology by the DOE Fossil Energy program, this is expected to change. We are building a quantum sensing instrument that will use the ability of the diamond NV- center to acquire nuclear magnetic resonance (NMR) signals from fluids and solute molecules close to the diamond surface with optical resolution or better. The initial goals are to measure the properties of interfacial solutions, such as viscosity and solution speciation, under ambient conditions. We are working with the Molecular Foundry at Berkeley Lab to grow few-monolayer thick silica and alumina layers on the diamond surface. The initial work will apply published protocols for optical NMR but we are also collaborating with UC-Berkeley Chemistry faculty Drs. Jeff Reimer, Ashok Ajoy and Alex Pines to develop new chemical sensing protocols. Ultimately, these quantum sensing methods will be integrated into an optical microscope compatible with biogeochemical studies, and extended to fiber-optic systems for field deployment.