Finite control of dielectric constant with magnetic field in Sm-doped Ba-Co U-type hexaferrites

Emergence of memory devices based on magneto-electric coupling leads us to investigate the dielectric and magneto-dielectric properties of U-type hexaferrites. (Ba1-3xSm2x)(4)Co2Fe36O60 ceramics, where x = 0.0-0.25, with the interval of 0.05, have been produced via auto combustion method and sintering at 1200 degrees C. Every sample has an R3m symmetric hexagonal structure, according to the XRD study. The samples with lower Sm content, i.e. 0.0 < x < 0.15 have better magnetic properties than the samples having 0.15 < x < 0.25. Impedance spectroscopy has been used to study dielectric characteristics. The sample with x = 0.15 at 1.2 T and 1000 Hz showed maximum magnetization and a magneto-electric coupling accompanied by a magnetic coefficient of about 104.9%, which is very high in case of hexaferrites. Therefore, these results will be fruitful from the application point of view.