Exploring the microwave assisted sol-gel synthesized multivalent doped thin films of iron oxide for detailed impedance and magnetodielectric response

Extensive research is carried out now a days to explore multifunctional materials for electronic, optoelectronic and spintronic devices. Multifunctionality that depends on the coupling between magnetic and electronic larization, is a big challenge particularly for electronic and spintronic applications. This research focuses on development of material and methodology to produce strong coupling between two polarizations/orders. iron oxide films are prepared by the combined effect of microwaves and sol-gel after irradiating the solution 720W. Multivalent doped sols are synthesized with variation in aluminum (Al) and cobalt (Co) concentrations the range of 2 to 10 wt%. Crystal phase change from maghemite to magnetite, at Al-Co content of 8 to 10 wt%, observed by XRD results. Phase transformation from maghemite to magnetite shows that probability of pancy of Al3+and Co2+ ions of vacancies on B and A sites is affected by the microwave irradiation. Structural phase transition is also accompanied by the increased saturation magnetization. Undoped thin films, maghemite, exhibit dielectric constant -100 (log f = 4.5). Various relaxation phenomena are observed impedance analyses. Room temperature magnetic and dielectric coupling is observed under multivalent doping conditions.