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arXiv · 2101.02192

A perpendicular field electromagnet with a 250mm access bore

A. P. Petrović·B. H. M. Smit·K. L. Fong·B. Satywali·X. Y. Tee·C. Panagopoulos
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Abstract

We present a laboratory electromagnet capable of generating magnetic fields up to $\pm$0.48T, specifically designed as a perpendicular flux source for thin film samples in an ambient environment. The magnet features a 250mm diameter clear access bore above the sample plane, thus offering compatibility with a wide variety of experimental apparatus. Despite its generous size, the magnet thermally dissipates less than 1kW at maximum field. A shaped ferromagnetic core is used to amplify and homogenize the field $\mathbf{B}$, leading to an estimated uniformity of $\pm$1.5mT ($\lesssim$0.3%) in $\left|\mathbf{B}\right|$ within a 28mm$^2$ zone at maximum field. The sample stage is thermally regulated and isolated from the magnet, enabling temperature control with $\pm$5mK precision even at elevated magnetic fields.

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A. P. Petrović, B. H. M. Smit, K. L. Fong, B. Satywali, X. Y. Tee, C. Panagopoulos. 2021-01-06. A perpendicular field electromagnet with a 250mm access bore. https://doi.org/10.1063/5.0027913

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