Surface-resistance measurements using superconducting stripline resonators.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Electrical Engineering

Background:

• Accurate measurement of surface resistance is crucial for understanding conductive materials.
• Existing methods often require complex calibration and are limited in frequency range.

Purpose of the Study:

• To present a novel method for measuring absolute surface resistance of conductive samples at GHz frequencies.
• To enable direct calculation of surface resistance for bulk samples without additional calibration.

Main Methods:

• Utilizing superconducting lead stripline resonators operating at 1-6 K.
• Implementing a correction method for experimental background using TEM properties of external cabling.
• Applying the method to reference materials: gold, tantalum, and tin.

Main Results:

• Demonstrated direct calculation of surface resistance for bulk samples.
• Observed phenomena including the anomalous skin effect and conventional superconductivity in tested materials.
• Extracted complex optical conductivity for a lead resonator, revealing a coherence peak and superconducting gap.

Conclusions:

• The presented method offers a simplified and direct approach to GHz surface resistance measurements.
• The technique is versatile, applicable to various conductive materials and phenomena.
• Provides insights into material properties like optical conductivity and superconducting gaps.