Nuclear magnetic resonance spectroscopy on a (5-nanometer)3 sample volume

Area of Science:

• Physics
• Chemistry
• Materials Science

Background:

• Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful analytical technique.
• Applying NMR to nanoscale samples has been challenging, typically requiring extremely low temperatures and significant experimental effort.
• Previous methods lacked the sensitivity to detect signals from very small sample volumes.

Purpose of the Study:

• To demonstrate the feasibility of performing NMR spectroscopy on nanoscale samples under ambient conditions.
• To develop a novel method for detecting NMR signals from extremely small volumes of organic matter.

Main Methods:

• Utilized a single nitrogen-vacancy (NV) defect center in diamond as an atomic-size magnetic field sensor.
• Embedded the NV center approximately 7 nanometers beneath the diamond surface.
• Placed various fluid and solid organic samples on the diamond surface for analysis.
• Recorded NMR spectra from a (5-nanometer)^3 voxel of the sample.

Main Results:

• Successfully detected NMR signals from nanoscale volumes of organic samples at ambient temperatures.
• The detection volume contained as few as 10^4 nuclear spins.
• The method achieved sensitivity with only 10^2 statistically polarized spins.

Conclusions:

• Demonstrated a new capability for nanoscale NMR spectroscopy under ambient conditions.
• The nitrogen-vacancy center in diamond serves as a highly sensitive sensor for detecting NMR signals from minimal spin ensembles.
• This technique opens new avenues for chemical and physical analysis of materials at the nanoscale.