Dobrovolskiy Oleksandr V, Sachser Roland, Bunyaev Sergey A, Navas David, Bevz Volodymyr M, Zelent Mateusz, Śmigaj Wojciech, Rychły Justyna, Krawczyk Maciej, Vovk Ruslan V, Huth Michael, Kakazei Gleb N
Physikalisches Institut , Goethe University , 60438 Frankfurt am Main , Germany.
Physics Department , V. Karazin National University , 61077 Kharkiv , Ukraine.
ACS Appl Mater Interfaces. 2019 May 15;11(19):17654-17662. doi: 10.1021/acsami.9b02717. Epub 2019 May 1.
Local modification of magnetic properties of nanoelements is a key to design future-generation magnonic devices in which information is carried and processed via spin waves. One of the biggest challenges here is to fabricate simple and miniature phase-controlling elements with broad tunability. Here, we successfully realize such spin-wave phase shifters upon a single nanogroove milled by a focused ion beam in a Co-Fe microsized magnonic waveguide. By varying the groove depth and the in-plane bias magnetic field, we continuously tune the spin-wave phase and experimentally evidence a complete phase inversion. The microscopic mechanism of the phase shift is based on the combined action of the nanogroove as a geometrical defect and the lower spin-wave group velocity in the waveguide under the groove where the magnetization is reduced due to the incorporation of Ga ions during the ion-beam milling. The proposed phase shifter can easily be on-chip integrated with spin-wave logic gates and other magnonic devices. Our findings are crucial for designing nanomagnonic circuits and for the development of spin-wave nano-optics.
纳米元件磁性的局部调控是设计下一代磁子器件的关键，在这类器件中信息通过自旋波进行传输和处理。这里最大的挑战之一是制造具有广泛可调性的简单且微型的相位控制元件。在此，我们通过聚焦离子束在Co-Fe微米级磁子波导中铣出的单个纳米槽成功实现了此类自旋波移相器。通过改变槽深和面内偏置磁场，我们连续调节自旋波相位，并通过实验证明了完全的相位反转。相移的微观机制基于纳米槽作为几何缺陷的综合作用，以及在槽下方波导中自旋波群速度较低的情况，在离子束铣削过程中由于Ga离子的掺入，此处的磁化强度降低。所提出的移相器能够轻松地与自旋波逻辑门及其他磁子器件进行片上集成。我们的研究结果对于设计纳米磁子电路以及自旋波纳米光学的发展至关重要。
