Excellent microwave and magnetic properties of La-Cu substituted Ba-hexaferrites prepared by ceramic process

TL;DR

This study reports the synthesis of La-Cu substituted barium hexaferrites with exceptional microwave and magnetic properties, demonstrating their potential for advanced magnetic applications.

Contribution

It introduces a ceramic process to produce textured Ba-hexaferrites with record magnetic anisotropy and low FMR linewidth, validated by multiple measurement techniques.

Findings

High magnetic anisotropy field of 14.6kOe

Lowest FMR linewidth of 401Oe at Q-band

Good agreement between theoretical and experimental values

Abstract

We demonstrate exceptional microwave magnetic performance of crystallographycally textured barium hexaferrites prepared by conventional ceramic method. Vibrating sample magnetometer (VSM) and rectangular cavity perturbation measurements indicate that bulk Ba0.8La0.2Fe11.2Cu0.2O19 samples exhibit a strong magnetic anisotropy field Ha of 14.6kOe, the highest remanent magnetization of 3.96kGs, and the lowest ferromagnetic resonance (FMR) linewidth of 401Oe with zero applied bias field at Q-band. Broadband millimeter-wave transmittance measurements determined the complex permeability and permittivity. The remanent magnetization, anisotropy field Ha, and effective linewidth were also estimated based on Schlomann's theory of the complex permeability. These calculated values are in good agreement with the VSM and FMR measurements.