Baek, Kyungnae Doh, Sang-Gil Jeong, Wonmin Lee, OukJae Hyun, Jerome K. 2024-01-19T14:31:13Z 2024-01-19T14:31:13Z 2021-09-05 2021-06-25 0925-8388 https://pubs.kist.re.kr/handle/201004/116841 The need to block specific frequencies of electromagnetic (EM) waves in complex communication systems such as in wireless autonomous vehicles with EM absorption films is becoming increasingly important. Increasing safety requirements necessitate that the films operate with highly precise and accurate frequency selectivity, while commercial specifications demand extremely small thicknesses. Herein, we demonstrate that the mixing of ferroelectric BaTiO3 particles into a soft magnetic FeSiAl flake composite, followed by heat-pressing, not only enhances the electric permittivity,., which can be further tuned by oxygen vacancy engineering, but also increases the effective magnetic permeability, mu, by geometrically-induced suppression of eddy current losses and stressed-induced enhancements in the saturation magnetization. The enhanced refractive index (root epsilon mu) in conjunction with the dielectric and magnetic loss leads to perfect absorption at a unique thickness that is similar to 15-44% thinner than its magnetic counterpart and an order of magnitude less than a quarter wavelength. These results pave the way for developing highly precise frequency selective absorption films with subwavelength thicknesses, and also provide strategies for reducing the soft magnetic material content in high-frequency ferromagnetic applications for decreased materials cost and weight. (C) 2021 Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE SA Subwavelength electromagnetic wave absorption with ferroelectric particles that enhance the magnetic permeability in magnetodielectric composites Article 10.1016/j.jallcom.2021.159075 1 JOURNAL OF ALLOYS AND COMPOUNDS, v.867 JOURNAL OF ALLOYS AND COMPOUNDS 867 scie scopus 000630276200094 2-s2.0-85100988033 Chemistry, Physical Materials Science, Multidisciplinary Metallurgy & Metallurgical Engineering Chemistry Materials Science Metallurgy & Metallurgical Engineering Article Magnetodielectric Permeability Permittivity Electromagnetic wave absorption FeSiAl