Microwave Absorption Properties of Cobalt-Zirconium Doped Strontium Hexaferrites in Ku-Frequency Band

In this article, microwave electromagnetic properties of doped strontium hexaferrites have been investigated in Ku microwave frequency band (12.4-18 GHz), along with their performance as microwave absorbing materials. Vector network analyzer has been used for characterization of cobalt-zirconium substituted strontium hexaferrites Sr(CoZr)(x)Fe(12-2x)O19 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0), synthesized using sol-gel method. Real parts of permittivity and permeability have shown very small variations up to 16 GHz. There has been a dip in spectrum of real part of permittivity and a peak in spectrum of real part of permeability at the same frequency in 16-18 GHz range for every composition. Regarding the electromagnetic wave absorption, all the six prepared compositions have potential (>= 90% absorption) for usage in suppressing electromagnetic pollution. The composition with x = 1.0 has achieved the highest -10 dB absorption bandwidth from 15 to 18 GHz frequency. The realization of absorbing materials with maximum absorption is related to the phenomenon of impedance matching and high electromagnetic losses. The correlation of absorption peaks with attenuation constant, wave impedance and complex thickness has also been studied.