A geometry-independent moment correction method for the MPMS3 SQUID-based magnetometer

authors	Amorim, CO; Mohseni, F; Dumas, RK; Amaral, VS; Amaral, JS
nationality	International
journal	MEASUREMENT SCIENCE AND TECHNOLOGY
author keywords	magnetometry; SQUID; geometry effects; radial offset
abstract	Modern superconducting quantum interference device (SQUID) magnetometers enable fully automated measurements with currently unmatched sensitivity. The measured moment values are, however, prone to deviations from their actual value due to geometric effects, namely sample size, shape, and radial offset. The current procedure to correct these geometric effects, for the magnetic property measurement 3 (MPMS3) magnetometer, is based on an available simulation tool, valid for both SQUID-VSM and DC-scan methods. Still, determining the correction factor requires samples with well-defined geometric shapes together with accurate sample dimensions and the usually difficult to determine radial offset. There is no established solution to correct geometry effects of irregularly shaped samples or unknown radial offsets. In this work, we find a systematic relation between the difference of SQUID-VSM and DC-scan measurements and their corresponding correction factors for the MPMS3. This relation follows a clear trend, independent of sample geometry and radial offset, for a given pair of DC-scan length and SQUID-VSM amplitude values. Exploiting this trend, a geometry-independent correction method is presented and validated by measurements of two different geometries of the same Al piece, two different radial offsets of a Ni square, and metallic Fe powder using a far from optimal sample mounting.
publisher	IOP PUBLISHING LTD
issn	0957-0233
isbn	1361-6501
year published	2021
volume	32
issue	10
digital object identifier (doi)	10.1088/1361-6501/ac0d23
web of science category	5
subject category	Engineering, Multidisciplinary; Instruments & Instrumentation
unique article identifier	WOS:000670044000001