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arXiv · 2508.07929

AC Magnetometry Loop Tracer Compatible with Magnetic Calorimetry for Power Loss Analysis

Thomas Veile·Michael Harmel·Mathias Zambach·Philip Holm·Frederik L. Durhuus·Cathrine Frandsen
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Abstract

Magnetic nanoparticles (MNPs) have garnered significant attention for various applications in the high-kHz-to-MHz range, although their magnetic characterization at these operational conditions has been limited. However, a number of recent studies have showcased high-frequency and high-field amplitude AC magnetometry loop tracers capable of retrieving the magnetic AC hysteresis curve and the associated magnetic properties. In this paper, we present an easily constructable loop tracer that is retrofitted into an existing AC calorimetry setup. This enables the loop tracer to function simultaneously with the AC calorimetry setup and also to be run as a high-frequency AC susceptometer. The loop tracer is shown to work in the frequency range 160-922 kHz with maximum applied fields from 18 to 46 mT depending on the frequency. An iron oxide nanoflower sample is used to test the loop tracer, showcasing high reproducibility in measured magnetic parameters as well as quantitative agreement between the different measurement methods in the setup.

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Thomas Veile, Michael Harmel, Mathias Zambach, Philip Holm, Frederik L. Durhuus, Cathrine Frandsen. 2025-08-11. AC Magnetometry Loop Tracer Compatible with Magnetic Calorimetry for Power Loss Analysis. https://arxiv.org/abs/2508.07929

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