RT info:eu-repo/semantics/article T1 Broadband ferromagnetic resonance in Mn-doped Li ferrite nanoparticles A1 Hernández Gómez, Pablo A1 Muñoz Muñoz, José María A1 Almeida Valente, Manuel A1 Fernandes Graça, Manuel Pedro K1 Magnetic materials K1 Materiales magnéticos K1 Oxide K1 Óxido K1 Sol-gel processes K1 Procesos sol-gel K1 2202.08 Magnetismo AB 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 250–1000 °C range. XRD confirms spinel formation with particle size in the 15–200 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 m T 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. PB Elsevier SN 0025-5408 YR 2019 FD 2019 LK http://uvadoc.uva.es/handle/10324/37264 UL http://uvadoc.uva.es/handle/10324/37264 LA eng NO Materials Research Bulletin, 2019, vol. 112. p. 432-437 NO Producción Científica DS UVaDOC RD 23-dic-2024