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 polarization, is a big challenge particularly for electronic and spintronic applications. This research focuses on the development of material and methodology to produce strong coupling between two polarizations/orders. Thin iron oxide films are prepared by the combined effect of microwaves and sol-gel after irradiating the solution at 720W. Multivalent doped sols are synthesized with variation in aluminum (Al) and cobalt (Co) concentrations in the range of 2 to 10 wt%. Crystal phase change from maghemite to magnetite, at Al–Co content of 8 to 10 wt%, is observed by XRD results. Phase transformation from maghemite to magnetite shows that probability of occupancy of Al³⁺and Co²⁺ ions of vacancies on B and A sites is strongly affected by the microwave irradiation. Structural phase transition is also accompanied by the increased saturation magnetization, i.e. ∼600 emu/cm³. Undoped thin films, i.e. maghemite, exhibit dielectric constant ∼100 (log f = 4.5). Various relaxation phenomena are observed in impedance analyses. Room temperature magnetic and dielectric coupling is observed under multivalent doping conditions.

如今，人们正在进行广泛的研究，探索用于电子、光电子和自旋电子器件的多功能材料。取决于磁极化和电子极化之间耦合的多功能性是一个巨大的挑战，特别是对于电子和自旋电子应用而言。这项研究的重点是开发在两个极化/秩序之间产生强耦合的材料和方法。在720W照射溶液后，通过微波和溶胶-凝胶的联合作用制备氧化铁薄膜。合成多价掺杂溶胶，铝 (Al) 和钴 (Co) 浓度变化范围为 2 至 10 wt%。通过 XRD 结果观察到，当 Al-Co 含量为 8 至 10 wt% 时，从磁赤铁矿到磁铁矿的晶相变化。从磁赤铁矿到磁铁矿的相变表明，Al ³⁺和Co ²⁺离子占据B 和A 位点空位的概率受到微波辐射的强烈影响。结构相变还伴随着饱和磁化强度的增加，即~600 emu/cm ³。未掺杂的薄膜，即磁赤铁矿，介电常数~100（log f  = 4.5）。在阻抗分析中观察到各种弛豫现象。在多价掺杂条件下观察到室温磁和介电耦合。