Controlling polarization of spintronic THz emitter by remanent magnetization texture
Controlling polarization of spintronic THz emitter by remanent magnetization texture
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DOI：
10.1063/5.0096252
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发表时间：
2022-07
影响因子：
4
通讯作者：
W. Wu;S. Lendínez;M. T. Kaffash;R. Schaller;H. Wen;M. Jungfleisch
中科院分区：
文献类型：
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作者：
W. Wu;S. Lendínez;M. T. Kaffash;R. Schaller;H. Wen;M. Jungfleisch
太赫兹（THz）科学和技术促进了广泛应用的快速发展，并扩大了基础科学的前沿。自旋电子太赫兹发射器提供了概念上的优势，因为磁性层中的自旋取向可以通过外部施加的磁场或通过由磁性元件的特定形状确定的内部磁场分布来容易地控制。在这里，我们报告了一个可切换的太赫兹源的基础上微图案化的磁性异质结构驱动的飞秒激光脉冲。我们表明，极化状态的精确可调谐性是由微结构的形状所决定的磁性层的基本磁化织构促进的。这些结果也揭示了非均匀磁化状态在磁性异质结构中产生超快自旋电流的潜在物理机制。我们的研究结果表明，线偏振太赫兹波的发射可以通过使用偏置磁场饱和样品来打开和关闭，为具有广泛潜在应用的集成片上太赫兹器件开辟了迷人的前景。
Terahertz (THz) sciences and technologies have contributed to a rapid development of a wide range of applications and expanded the frontiers in fundamental science. Spintronic terahertz emitters offer conceptual advantages since the spin orientation in the magnetic layer can be easily controlled either by the externally applied magnetic field or by the internal magnetic field distribution determined by the specific shape of the magnetic elements. Here, we report a switchable terahertz source based on micropatterned magnetic heterostructures driven by femtosecond laser pulses. We show that the precise tunability of the polarization state is facilitated by the underlying magnetization texture of the magnetic layer that is dictated by the shape of the microstructure. These results also reveal the underlying physical mechanisms of a nonuniform magnetization state on the generation of ultrafast spin currents in the magnetic heterostructures. Our findings indicate that the emission of the linearly polarized THz waves can be switched on and off by saturating the sample using a biasing magnetic field, opening fascinating perspectives for integrated on-chip THz devices with wide-ranging potential applications.