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Updated: Sep 26, 2025

Fabrication and Characterization of Superconducting Resonators
Published on: May 21, 2016
Application of Counter-wound Multi-arm Spirals in HTS Resonator Design
Taylor L Johnston1, Arthur S Edison2, Vijaykumar Ramaswamy3
1National High Magnetic Laboratory, Tallahassee, FL 32310, USA and also with the Department of Chemistry and Biochemistry, Florida State University.
Abstract:
Significant sensitivity improvements have been achieved by utilizing high temperature superconducting (HTS) resonators in nuclear magnetic resonance (NMR) probes. Many nuclei such as 13C benefit from strong excitation fields which cannot be produced by traditional HTS resonator designs. We investigate the use of double-sided, counter-wound multi-arm spiral HTS resonators with the aim of increasing the excitation field at the required nuclear Larmor frequency for 13C. When compared to double-sided, counter-wound spiral resonators with similar geometry, simulations indicate that the multi-arm spiral version develops a more uniform current distribution. Preliminary tests of a two-arm resonator indicate that it may produce a stronger excitation field.
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