Nuclear magnetic resonance measurements in dynamically controlled field pulse
Y Ihara1, K Hayashi1, T Kanda2
1Department of Physics, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
The Review of Scientific Instruments
|December 2, 2021
Summary
We developed a new nuclear magnetic resonance (NMR) spectrometer using software-defined radio for pulsed magnetic fields. This breakthrough enables precise measurements, like nuclear spin-lattice relaxation rates, in extreme magnetic environments.
Area of Science:
- Physics
- Chemistry
- Materials Science
Background:
- Accessing magnetic fields over 50 Tesla (T) typically requires pulsed-field technology.
- Conducting nuclear magnetic resonance (NMR) experiments in pulsed magnetic fields is challenging due to rapidly changing field strengths.
Purpose of the Study:
- To present a versatile NMR spectrometer architecture utilizing software-defined radio technology.
- To enable NMR experiments in dynamically controlled pulsed magnetic fields, overcoming previous limitations.
Main Methods:
- Developed a novel NMR spectrometer architecture integrating software-defined radio.
- Implemented dynamically controlled field pulses to create quasi-steady field conditions at the pulse peak.
- Utilized NMR spectroscopy as a high-precision magnetometer to verify field pulse reproducibility.
- Performed nuclear spin-lattice relaxation rate (1/T1) measurements and NMR spectrum analysis using frequency-sweep and field-sweep modes.
Main Results:
- Successfully performed NMR experiments in dynamically controlled pulsed magnetic fields.
- Confirmed the high reproducibility of field pulses, enabling precise measurements.
- Achieved the first measurement of the nuclear spin-lattice relaxation rate (1/T1) in pulsed magnetic fields without dynamic field control.
- Demonstrated both frequency-sweep and field-sweep modes for NMR spectrum measurement, providing guidance on mode selection based on sample properties.
Conclusions:
- The developed NMR spectrometer with dynamic field control facilitates experiments in quasi-steady field conditions within pulsed magnetic fields.
- This technology enables previously inaccessible measurements, such as 1/T1, in extreme magnetic fields.
- Further advancements in long-duration field pulses promise to revolutionize microscopic measurements in ultra-high magnetic fields.
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