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Updated: Jan 14, 2026
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Rapid Repetition Rate Fluctuation Measurement of Soliton Crystals in a Microresonator
Published on: December 15, 2021
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Sample-accessible multi-resonance X-band EPR triple ring resonator
Chun Him Lee1, Meltem Elitaş2, Jan G Korvink1
1Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, 76344, Germany.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|October 17, 2025
Summary
Researchers developed a novel triple-ring micro-resonator for electron paramagnetic resonance (EPR) spectroscopy. This device enables sensitive, high-throughput analysis of small samples with improved performance.
Area of Science:
- Physics
- Chemistry
- Materials Science
Background:
- Micro-resonators enable electron paramagnetic resonance (EPR) spectroscopy for mass-limited samples.
- Planar resonators offer accessible sample environments for in situ and operando experiments.
Purpose of the Study:
- To introduce a novel triple-ring micro-resonator structure for enhanced EPR spectroscopy.
- To leverage miniaturization and sample accessibility for advanced characterization.
Main Methods:
- Designed and fabricated a triple-ring micro-resonator structure.
- Utilized cascading ring resonators to enhance the quality factor (Q-factor).
- Implemented relative translations for tuning and isolation of resonances.
Main Results:
- Achieved three simultaneously operating X-band channels (8-11 GHz) with 50 nL sample volume per channel.
- Demonstrated a maximum spin sensitivity of 1.18×10^8 Spin/Hz^1/2.
- Obtained a Q-factor of 73 for the center resonance (9.45 GHz) with passive reflectors.
Conclusions:
- The novel triple-ring resonator offers improved sensitivity and sample accessibility for EPR spectroscopy.
- Cascading resonators enhances Q-factor, enabling more precise measurements.
- The design is scalable for high-throughput parallel EPR spectroscopy.
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