We describe the magnetic domain structures and magnetoelectric coupling in self-assembled BiFeO₃–CoFe₂O₄ (BFO–CFO) nanocomposite thin films grown on (110)-LaAlO₃ substrates, consisting of CFO slab-shaped crystals (nanofins) embedded in a BFO matrix. The nanofins exhibit magnetic single-domain states with in-plane magnetization along their length due to shape and magnetoelastic anisotropies. The piezoresponse of the BFO matrix is affected by applying an in-plane hard axis magnetic field, indicating magnetoelectric coupling within the multiferroic composite. Conversely, an applied electric field leads to the magnetic reversal of a fraction of the nanofins as the strain transferred from the BFO alters the magnetic anisotropy, enabling switching driven by magnetostatic interactions.

中文翻译：

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自组装BiFeO3-CoFe2O4纳米复合材料在（110）-LaAlO3衬底上的磁电耦合

我们描述了在（110）-LaAlO ₃上生长的自组装BiFeO ₃ -CoFe ₂ O ₄（BFO-CFO）纳米复合薄膜中的磁畴结构和磁电耦合。基板，由嵌入BFO矩阵中的CFO平板状晶体（nanofins）组成。由于形状和磁弹性各向异性，纳米鳍沿其长度具有平面内磁化的磁性单畴态。BFO矩阵的压电响应会受到施加面内硬轴磁场的影响，这表明多铁性复合材料内部的磁电耦合。相反，由于从BFO传递的应变改变了磁各向异性，因此施加的电场导致一部分纳米鳍片发生磁反转，从而实现了由静磁相互作用驱动的开关。