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Updated: Sep 15, 2025
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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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Temperature-Dependent Dynamic Nuclear Polarization of Diamond
Gevin von Witte1,2, Aaron Himmler2, Konstantin Tamarov3
1Institute for Biomedical Engineering, University and ETH Zurich, 8092 Zurich, Switzerland.
Summary
Dynamic nuclear polarization (DNP) enhances nuclear magnetic resonance signals significantly in diamond. Experiments show polarization up to 38% at 1.7 K, with temperature-dependent profiles and polarization mechanisms identified.
Area of Science:
- Solid-state physics
- Quantum information science
- Materials science
Background:
- Dynamic nuclear polarization (DNP) is a technique to enhance nuclear magnetic resonance (NMR) signals.
- Nitrogen-vacancy (NV) centers and other nitrogen defects are common in diamond and influence its spin properties.
- Understanding spin dynamics in diamond is crucial for quantum sensing and computing applications.
Purpose of the Study:
- To investigate carbon-13 (13C) DNP in diamond across a range of temperatures and magnetic fields.
- To characterize the temperature dependence of DNP profiles and nuclear polarization enhancements.
- To elucidate the underlying mechanisms of polarization transfer and the role of electron paramagnetic resonance (EPR) in diamond.
Main Methods:
- 13C DNP experiments were conducted in diamond at 3.4 and 7 Tesla static magnetic fields.
- Experiments covered a temperature range from 300 K down to 1.7 K.
- Longitudinal-detected electron paramagnetic resonance (EPR) was used to probe electron spin properties.
Main Results:
- Nuclear polarization enhancements between 100 and 600 were observed, reaching 38% polarization at 1.7 K and 7 T.
- A strong temperature dependence of DNP profiles was noted, with broad lines at low temperatures and structured features at room temperature.
- An additional temperature-dependent electron line was detected via EPR, potentially linked to clustered P1 centers or other nitrogen defects, affecting spectral asymmetry.
Conclusions:
- 13C nuclei in diamond are primarily polarized through direct hyperfine-mediated polarization transfer.
- Nuclear spin diffusion plays a minimal role in the observed polarization.
- The findings provide insights into spin dynamics in diamond, relevant for DNP-enhanced NMR spectroscopy and quantum technologies.
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