论文标题
基于CO $ _2 $ mnge伪旋转阀的纳米接触涡流振荡器
Nanocontact vortex oscillators based on Co$_2$MnGe pseudo-spin valves
论文作者
论文摘要
我们介绍了一项基于伪旋转阀的磁性纳米接触中涡流动力学的实验研究，其中包括CO $ _2 $ MNGE Heusler化合物。这些膜是通过分子束外延生长的，在该分子束上延伸，并在该分子束上进行了精确的化学计量控制和量身定制的堆叠顺序，使我们能够将底部的铁磁层定义为参考层，而自由层和参考层之间的耦合最小。使用纳米注册技术制造20 nm直径的纳米接触，从而导致由自旋转移扭矩产生的涡旋自我维持的旋转，高于某个当前阈值。通过结合频率和时间域测量值，我们表明可以观察到不同类型的自旋转移诱导的与与磁涡流配置相关的不同模式相关的动力学，例如，除了通常的回旋模式外，还出现了模式跳跃，模式的共存和模式灭绝。
We present an experimental study of vortex dynamics in magnetic nanocontacts based on pseudo spin valves comprising the Co$_2$MnGe Heusler compound. The films were grown by molecular beam epitaxy, where precise stoichiometry control and tailored stacking order allowed us to define the bottom ferromagnetic layer as the reference layer, with minimal coupling between the free and reference layers. 20-nm diameter nanocontacts were fabricated using a nano-indentation technique, leading to self-sustained gyration of the vortex generated by spin-transfer torques above a certain current threshold. By combining frequency- and time-domain measurements, we show that different types of spin-transfer induced dynamics related to different modes associated to the magnetic vortex configuration can be observed, such as mode hopping, mode coexistence and mode extinction appear in addition to the usual gyration mode.
