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DOE OSTI · 2472597

Material Characterization Study of Magnetite Nanocrystals for RF Sensing

Sherburne, Michael D.·Dreier, Timothy A.·Klitsner, Benjamin H.·Huber, Dale L.·Ivanov, Sergei A.·Parks, Chris·Simons, Matt T.·Schamiloglu, Edl
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Abstract

Magnetite nanocrystals show promise for electrically small gigahertz frequency applications, which could lead to miniaturizing transformer cores and new sensing technologies. This work presents a rigorous radiofrequency characterization of these nanocrystals using vector network analyzer (VNA) ferromagnetic resonance (FMR) measurements. For the first time, two different average diameters of Fe 3 O 4 nanocrystals are investigated (7.3 and 20.2 nm). When the VNA–FMR results were compared to micromagnetic simulations, the magnetic anisotropy (K 1 ) deviated from the ideal mean orientation value of K 1 /2 to K 1 /80 for the 7.3 nm nanocrystal. In contrast, the obtained magnetic anisotropy in 20.2 nm nanocrystals slightly deviated to K 1 /11 due to less structural deformations. These findings resulted in a newly proposed methodology for an approximate simulation based on VNA–FMR measurements. In addition, this work estimates the approximate amount of nanocrystals needed to measure a useful VNA–FMR spectrum.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYInorganic and Physical ChemistryMaterial Sciencemagnetic materialsmagnetic propertiesmagnetitematerialspower

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Sherburne, Michael D., Dreier, Timothy A., Klitsner, Benjamin H., Huber, Dale L., Ivanov, Sergei A., Parks, Chris, Simons, Matt T., Schamiloglu, Edl. 2024-09-24. Material Characterization Study of Magnetite Nanocrystals for RF Sensing. https://doi.org/10.1021/acsomega.4c04589

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