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arXiv · 2402.12096

Broadband ferromagnetic resonance in Mn-doped Li ferrite nanoparticles

P. Hernandez-Gomez·J. M. Muñoz·M. A. Valente·M. P. F. Graça
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Abstract

Lithium ferrites are well known materials due to their numerous technological applications especially in microwave devices. Mn-doped lithium ferrite nanoparticles were prepared by sol-gel technique by means of Pechini method, and then annealed at different temperatures in 250 to 1000 {\deg}C range. XRD confirms spinel formation with particle size in the 15 to 200 nm range, with increased size with annealing temperature. Microwave magnetoabsorption data of annealed lithium ferrite nanoparticles, obtained with a broadband system based on a network analyzer operating up to 8.5 GHz are presented. At fields up to 200 mT we can observe a broad absorption peak that shifts to higher frequencies with magnetic field according to ferromagnetic resonance theory. The amplitude of absorption, up to 85%, together with the frequency width of about 4.5 GHz makes this material suitable as wave absorber. Samples annealed at higher temperatures show a behaviour similar to polycrystalline samples, thus suggesting their multidomain character

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P. Hernandez-Gomez, J. M. Muñoz, M. A. Valente, M. P. F. Graça. 2024-02-19. Broadband ferromagnetic resonance in Mn-doped Li ferrite nanoparticles. https://doi.org/10.1016/j.materresbull.2018.09.005

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