Sharma Sanchar, Muralidharan Bhaskaran, Tulapurkar Ashwin
Department of Electrical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
Sci Rep. 2015 Sep 30;5:14647. doi: 10.1038/srep14647.
We propose a new mechanism and a related device concept for a robust, magnetic field tunable radio-frequency (rf) oscillator using the self oscillation of a magnetic domain wall subject to a uniform static magnetic field and a spatially non-uniform vertical dc spin current. The self oscillation of the domain wall is created as it translates periodically between two unstable positions, one being in the region where both the dc spin current and the magnetic field are present, and the other, being where only the magnetic field is present. The vertical dc spin current pushes it away from one unstable position while the magnetic field pushes it away from the other. We show that such oscillations are stable under noise and can exhibit a quality factor of over 1000. A domain wall under dynamic translation, not only being a source for rich physics, is also a promising candidate for advancements in nanoelectronics with the actively researched racetrack memory architecture, digital and analog switching paradigms as candidate examples. Devising a stable rf oscillator using a domain wall is hence another step towards the realization of an all domain wall logic scheme.
我们提出了一种新机制和相关的器件概念，用于构建一个稳健的、磁场可调的射频（rf）振荡器，该振荡器利用磁畴壁在均匀静磁场和空间非均匀垂直直流自旋电流作用下的自振荡。当磁畴壁在两个不稳定位置之间周期性平移时，就会产生自振荡，一个位置处于同时存在直流自旋电流和磁场的区域，另一个位置则仅存在磁场。垂直直流自旋电流将其从一个不稳定位置推开，而磁场将其从另一个不稳定位置推开。我们表明，这种振荡在噪声环境下是稳定的，并且品质因数可以超过1000。动态平移的磁畴壁不仅是丰富物理现象的来源，而且对于纳米电子学的发展也是一个有前景的候选者，例如正在积极研究的赛道存储器架构、数字和模拟开关范例。因此，设计一种使用磁畴壁的稳定射频振荡器是迈向实现全磁畴壁逻辑方案的又一步。
