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Superconducting quantum interference device microsusceptometer balanced over a wide bandwidth for nuclear magnetic
A Vinante1, R Mezzena2, P Falferi1
1Istituto di Fotonica e Nanotecnologie, CNR - Fondazione Bruno Kessler, I-38123 Povo, Trento, Italy.
The Review of Scientific Instruments
|November 3, 2014
Summary
We developed a double balancing technique for Superconducting Quantum Interference Device (SQUID) microsusceptometers, enabling sensitive nuclear magnetic resonance (NMR) detection in microscale samples. This advancement allows for direct NMR detection from tiny samples with high magnetic field generation.
Area of Science:
- Physics
- Materials Science
- Quantum Sensing
Background:
- Superconducting Quantum Interference Device (SQUID) microsusceptometers are established tools for microscale magnetic property studies.
- SQUID devices offer potential for direct nuclear magnetic resonance (NMR) detection in micron-sized samples.
- Existing SQUID microsusceptometers face limitations in achieving low imbalance and wide bandwidth for NMR applications.
Purpose of the Study:
- To demonstrate a double balancing technique for SQUID microsusceptometers to achieve very low residual imbalance.
- To enable high-bandwidth, high-field magnetic field generation within SQUID loops for enhanced NMR detection.
- To showcase direct SQUID-detection of nuclear magnetic resonance (NMR) from microscale samples.
Main Methods:
- Implementation of a double balancing technique in SQUID microsusceptometer fabrication.
- Generation of AC magnetic fields up to 1 mT over a wide bandwidth (dc to a few MHz) within the SQUID loop.
- Direct detection of proton ((1)H) NMR signals from a glycerol droplet positioned on a 20 μm SQUID.
Main Results:
- Achieved very low residual imbalance in the SQUID microsusceptometer across a wide frequency range.
- Successfully generated strong AC magnetic fields (up to 1 mT) suitable for NMR experiments.
- Demonstrated direct SQUID-detection of (1)H NMR signals from a microscale glycerol sample.
Conclusions:
- The double balancing technique significantly improves SQUID microsusceptometer performance for NMR applications.
- This method enables sensitive, direct NMR detection from submicron and micron-sized samples.
- The developed SQUID microsusceptometer is a promising tool for microscale magnetic resonance studies.
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