Method to improve critical current density measurement of superconducting materials

Area of Science:

• Superconductivity
• Materials Science
• Electrical Engineering

Background:

• Critical current density (Jc) is crucial for superconducting material applications.
• The third harmonic voltage method offers a non-destructive way to measure Jc in high-temperature superconducting films.
• Existing methods face challenges in signal-to-noise ratio for REBa2Cu3O7-δ films.

Purpose of the Study:

• To propose and validate a double-sided measurement method for improving Jc measurements.
• To enhance the signal-to-noise ratio in third harmonic voltage measurements of superconducting films.
• To adapt the technique for REBa2Cu3O7-δ films and high critical current densities.

Main Methods:

• A double-sided measurement system integrating electromagnetic shielding and a 2-coil setup was developed.
• The Meissner effect was utilized to minimize harmonic voltage noise in the pickup coil.
• Performance was compared against a standard 2-coil system in the 100 Hz to 1000 Hz range.

Main Results:

• The double-sided method demonstrated a 10-20 dB increase in signal-to-noise ratio compared to the 2-coil system.
• Noise reduction in the pickup coil was achieved using the Meissner effect within the specified frequency range.
• The measurement bandwidth was expanded, enabling potential future low-frequency measurements.

Conclusions:

• The proposed double-sided measurement method significantly improves Jc measurement accuracy for superconducting films.
• This technique offers a pathway for developing advanced measurement systems for materials with high critical current densities.
• The method provides a foundation for future research into low-frequency measurements and enhanced superconducting film characterization.