2025/06/20 by Agarwal, Harshit, Uralska, Oleksandra, Billingsley, Jasmin +2
Engineering · Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #Magnetic Field Sensors Techniques #Physics Education (physics.ed-ph) #Physics of Superconductivity and Magnetism
paper · pdf · doi:10.48550/arxiv.2506.16709
openalex publication_date 2025/06/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Understanding the magnetic properties of matter plays a key role in materials physics. However, university education on fundamental magnetism is limited to a theoretical survey because of the lack of appropriate apparatus that can be applied for laboratory courses at the undergraduate level. In this work, we introduce an AC magnetometer based on the Colpitts self-oscillator with an inductor coil as a probe. We show that this type of self-oscillator can be adopted in a typical university laboratory course to learn the principles of magnetic measurement and to understand the fundamental magnetism of matter. We demonstrate the exceptional stability of the circuit with a working frequency range of ~10 kHz to 10 MHz and excellent performance to detect the diamagnetic signal from a superconductor at cryogenic temperature.