论文标题
伸长的天空作为旋转扭矩纳米振荡器和镁波导
Elongated Skyrmion as Spin Torque Nano-Oscillator and Magnonic Waveguide
论文作者
论文摘要
旋转扭矩纳米振荡器在近几十年以来，由于其在未来的微波通信技术和神经形态计算中的潜在应用，因此在理论上和实验中都对自旋扭矩进行了广泛的研究。在这项工作中，我们提出了一个基于空中的自旋扭矩纳米振荡器，该磁振荡器由空间均匀的直流电流驱动，在该电流中，Skyrmion被两个固定位点限制。与其他基于天空的振荡器不同，这些振荡器是由圆形运动或天空振动模式产生的，稳态振荡动作是通过伸长的天空元素的周期性变形产生的。通过微磁模拟，我们发现振荡频率取决于驱动电流，阻尼常数以及固定位点的特性。这种对直流电流的非线性响应被证明是通用的，并且在反孔米，天际和域壁的情况下也可以出现。此外，伸长的天空具有矩形状的域壁，也可以用作宏伟的波导。利用此波导中自旋波的传播，我们提出了逻辑门的设备设计并证明其性能。
Spin torque nano-oscillator has been extensively studied both theoretically and experimentally in recent decades due to its potential applications in future microwave communication technology and neuromorphic computing. In this work, we present a skyrmion-based spin torque nano-oscillator driven by a spatially uniform direct current, where the skyrmion is confined by two pinning sites. Different from other skyrmion-based oscillators that arise from the circular motion or the breathing mode of a skyrmion, the steady-state oscillatory motions are produced by the periodic deformation of an elongated skyrmion. Through micromagnetic simulations, we find that the oscillation frequency depends on the driving current, the damping constant as well as the characteristics of pinning sites. This nonlinear response to direct current turns out to be universal and can also appear in the case of antiskyrmions, skyrmioniums and domain walls. Furthermore, the elongated skyrmion possesses a rectangle-like domain wall, which could also serve as a magnonic waveguide. Utilizing the propagation of spin waves in this waveguide, we propose a device design of logic gate and demonstrate its performance.
