Study On Ferroelectric Control Fo Room-Temperature Ferromagnetism In β-FeSi₂/P（VDF-trFe）

With the development of silicon-based semiconductor materials,the design of electronic integrated devices is becoming more and more complicated and the functions of components are becoming more and more abundant.However,most semiconductor devices still emphasize on control of electronic charge degrees of freedom,and the regulating research for electronic spin degrees of freedom is still at an immature stage.At present,storage devices take magnetism as a major medium to possess distinct advantages in the aspect of read and record and large capacity storage.How to better play the role of magnetism in modern storage technology has become the mainstream development direction of modern storage technologyβ-FeSi2 is a strong magnetic semiconductor material at room temperature,and its magnetic properties are derived from dangling bonds of iron on crystal planes {100}and {011}.We hope that the coupling structure of β-FeSi2/P(VDF-trFe)can be used to achieve effective regulation of ferromagnetism at room temperature while retaining the remanent polarization state of ferroelectric materials P(VDF-trFe).In the experiment,through chemical vapor deposition(CVD)method β-FeSi2 hexahedron particle with a grain size of 2 μm is fabricated and samples are coated with ferroelectric materials P(VDF-trFe)in a single layer with about 5 μm by means of spin-on PR coating.Then we applied a forward bias on the surface of the sample,which results in the accumulation of carrier at the ferromagnetic/ferroelectric interface At this time,the overall saturation magnetization of the system increased from 15 to 120 emu/g,and the resilience also increased from 780e to 120Oe.When the reverse bias was applied,the charge that had been accumulated in the coupling interface of the β-fesi2/P(VDF-trFe)was dissipated,the saturation magnetization of the system was reduced by 13 emu/g from 120 emu/g,and the coercivity was reduced from 120 to 60Oe.Besides,by the first principles calculation,we found out the relation between the number of β-FeSi2 particles and the electronic magnetic moment,which further verified that the magnetoelectric control of β-FeSi2/P(VDF-trFe)coupling structure is caused by the interface carrier modulation.At present,most of the work in this field focus on to realize the regulation effect by means of low temperature,while the magnetic regulation at room temperature is mainly concentrated in the modulation of the magnetic anisotropy of the iron atom layer.Therefore,our work of the apparent magnetic regulation in β-FeSi2/P(VDF-trFe)coupling structure has its unique and applied significance at room temperature.