Design and implementation of a low temperature, inductance based high frequency alternating current susceptometer

Area of Science:

• Condensed Matter Physics
• Materials Science
• Magnetism

Background:

• AC susceptibility is a key technique for probing magnetic properties.
• Low-temperature and high-frequency measurements are crucial for understanding complex magnetic phenomena.

Purpose of the Study:

• To report the implementation of a novel induction-based AC susceptometer.
• To detail its capabilities for low-temperature (2-300 K) and high-frequency (up to 3.5 MHz) measurements.
• To demonstrate its high sensitivity for magnetic moment resolution.

Main Methods:

• Induction-based AC susceptometer design with careful coil balancing.
• Calibration procedures for accurate measurements.
• Variable temperature control from 2 K to 300 K.
• High-frequency measurements up to 3.5 MHz.

Main Results:

• Achieved a sample magnetic moment resolution of 5 × 10^-10 Am² at 1 MHz.
• Successfully characterized the susceptometer's performance.
• Demonstrated functionality through measurements on spin ice (CdEr₂S₄) and iron oxide nanoparticles.

Conclusions:

• The developed AC susceptometer is a versatile tool for advanced magnetic characterization.
• Its high sensitivity and wide operating range facilitate the study of novel magnetic materials.
• The instrument is suitable for investigating spin ice systems and magnetic nanoparticles.