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Updated: May 8, 2026
16:20
Hyperpolarized Xenon for NMR and MRI Applications
Published on: September 6, 2012
Bulk nuclear polarization enhanced at room temperature by optical pumping
Ran Fischer1, Christian O Bretschneider, Paz London
1Department of Physics, Technion, Israel Institute of Technology, Haifa 32000, Israel.
Physical Review Letters
|August 20, 2013
Summary
Researchers enhanced bulk carbon-13 (13C) polarization in diamond at room temperature using optical pumping of nitrogen-vacancy centers. This novel technique offers a simple, promising method for nuclear hyperpolarization.
Area of Science:
- Solid-state physics
- Quantum optics
- Materials science
Background:
- Nitrogen-vacancy (NV) color centers in diamond are crucial for quantum sensing and information processing.
- Optical pumping of NV centers can induce spin polarization, but its application to bulk nuclear spin hyperpolarization is less explored.
Purpose of the Study:
- To investigate the feasibility of enhancing bulk carbon-13 (13C) nuclear polarization in diamond at room temperature via optical pumping of NV centers.
- To quantify the achieved polarization levels and assess their bulk nature.
Main Methods:
- Optical pumping of diamond crystals containing NV centers at a ~50 mT magnetic field.
- Utilizing anticrossings between electronic excited-state levels for polarization transfer.
- Transferring the optically pumped sample to a Nuclear Magnetic Resonance (NMR) setup for 13C detection.
- Analyzing line shape and relaxation measurements to confirm bulk polarization.
Main Results:
- Achieved a significant bulk 13C nuclear polarization of ~0.5% at room temperature.
- Demonstrated that this polarization is equivalent to thermal polarization at ~2000 T.
- Observed both positive and negative enhanced polarizations with a predictable dependence on the optical pumping magnetic field.
Conclusions:
- Optical pumping of NV centers provides a simple and effective room-temperature strategy for bulk 13C hyperpolarization in diamond.
- This technique represents a valuable addition to existing nuclear hyperpolarization methods.
- The findings open avenues for enhanced NMR spectroscopy and quantum sensing applications.
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