Design and development of a low temperature, inductance based high frequency ac susceptometer

TL;DR

This paper presents a novel low temperature, high frequency ac susceptometer capable of measuring magnetic properties up to 3.5 MHz across a wide temperature range, with high sensitivity demonstrated through example measurements.

Contribution

The paper introduces a new inductance-based susceptometer design that operates at high frequencies and low temperatures, with improved calibration and resolution capabilities.

Findings

Achieved measurement frequency up to 3.5 MHz.

Sample magnetic moment resolution of 5×10^{-10} Am^2 at 1 MHz.

Successful measurements on spin ice and nanoparticle samples.

Abstract

We report on the development of an induction based low temperature high frequency ac susceptometer capable of measuring at frequencies up to 3.5 MHz and at temperatures between 2 K and 300 K. Careful balancing of the detection coils and calibration have allowed a sample magnetic moment resolution of $5\times10^{-10} Am^2$ at 1 MHz. We will discuss the design and characterization of the susceptometer, and explain the calibration process. We also include some example measurements on the spin ice material CdEr$_2$S$_4$ and iron oxide based nanoparticles to illustrate functionality.