Multi-turn split-conductor transmission-line resonators

Area of Science:

• Physics
• Electrical Engineering
• Materials Science

Background:

• High-Q, thin-film, high-temperature superconducting probes are crucial for advanced Nuclear Magnetic Resonance (NMR) applications.
• Existing designs often rely on lumped tuning capacitors, which can limit performance and introduce losses.
• A need exists for alternative resonator architectures that are simpler to design and tune across a wide frequency range.

Purpose of the Study:

• To introduce and analyze the Multi-turn Split-Conductor Transmission-line Resonator (MSTR) as a viable alternative for NMR probes.
• To develop an analytical method for calculating the resonant frequency of MSTRs.
• To experimentally validate the design principles and calculations through fabricated resonators.

Main Methods:

• Design and theoretical analysis of MSTRs based on transmission-line theory.
• Development of an analytical formula for resonant frequency dependent on physical parameters.
• Fabrication of MSTRs on a double copper-clad substrate.
• Experimental measurement of resonant frequencies for fabricated MSTRs.

Main Results:

• MSTRs can operate across a wide range of NMR frequencies without external tuning components.
• An accurate analytical model was derived for predicting MSTR resonant frequencies.
• Experimental results for fabricated MSTRs showed good agreement with predicted values.

Conclusions:

• MSTRs provide a promising, capacitor-free architecture for high-Q superconducting NMR probes.
• The analytical calculation method simplifies the design process for MSTRs.
• This resonator design offers an advantageous alternative for achieving tunable NMR probe frequencies.