Opt Lett. 2018 Nov 15;43(22):5551-5554. doi: 10.1364/OL.43.005551.
In this Letter, all-optical generation of magnetization with arbitrary three-dimensional (3D) orientations is numerically demonstrated through the inverse Faraday effect (IFE) by using a reversing calculation method. The IFE-induced magnetization with an expected 3D orientation is initially conceived by coherently configuring two orthogonally arranged electric dipoles with a phase difference of π/2 in the focal region of a to-be-determined incident light field. Based on the dipole antenna theory, this required incident light field can be deduced analytically according to the orientations of the electric dipoles. By utilizing this field as illumination and reversing the field propagation, magnetization with the expected orientation can be obtained in the focal region through the IFE. Moreover, this method showcases a high magnetization orientation purity (greater than 93%) within the focal volume defined by the full width at half maximum when the numerical aperture of the focal lens is 0.95. This result demonstrates extended flexibility of magnetization manipulations in an all-optical fashion and possesses great potential in spintronics and all-optical magnetic recording.
在这封信件中，通过使用反转计算方法，数值证明了通过逆法拉第效应（IFE）实现任意三维（3D）取向的磁化的全光学产生。通过在待确定入射光场的焦区中以相位差π/2相干配置两个正交排列的电偶极子，最初设想了具有预期 3D 取向的 IFE 诱导磁化。基于偶极天线理论，可以根据电偶极子的取向来解析推导出所需的入射光场。通过利用该场作为照明并反转场传播，可以通过 IFE 在焦区中获得具有预期取向的磁化。此外，当焦透镜的数值孔径为 0.95 时，该方法在由半峰全宽定义的焦区体积内展示出了大于 93%的高磁化取向纯度。该结果证明了以全光方式进行磁化操作的扩展灵活性，并且在自旋电子学和全光磁记录中具有很大的潜力。
