Development of a variable frequency, low current, low volume hysteresis loop tracer

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A variable frequency, low current, low cost, high sensitivity magnetometer has been developed. The system uses three MnZn ferrite rods to enhance the maximum field achievable by up to a factor 6 compared to the case where no ferrites are used. The system was tested using a suspension of magnetite nanoparticles in water. The magnetic response of the particles was investigated as a function of the maximum applied field and the frequency of operation. Volumes as low as 7 µl are required to obtain signal to noise ratio of 8(47 kHz)/3(111 kHz) for a fluid with a saturation magnetisation of 1.07 emu/cm3. Fields as high as 420 Oe can be applied by passing a current as low as 2.5 A through the primary coil at all operating frequencies.
Original languageEnglish
Article number169249
Number of pages7
JournalJournal of Magnetism and Magnetic Materials
Early online date9 Mar 2022
Publication statusE-pub ahead of print - 9 Mar 2022

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© 2022 Elsevier B.V. All rights reserved. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Funded by EPSRC via their Impact Acceleration Account (EP/R51181X/1).

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