自旋器件中的自旋动力学:微波领域应用的新兴科学

自旋电子学指通过控制和利用电子自旋(而不是电荷)获得一系列新颖性能的研究领域。自旋电子器件已经成功地应用于计算机硬盘驱动器和磁性随机存储器,对IT行业的发展产生了深远的影响。这些应用都是基于自旋极化传输效应,即具有固定自旋取向的电子穿过磁性异质结所发生的相关效应。目前,在将微波和自旋极化传输联系起来的自旋器件中的自旋动力学研究,为研制尺寸远远小于微波波长的新型微波器件提供了巨大的潜能。在这篇综述中,首先简单地介绍了自旋器件的概念;接着研究了微波实验来研究自旋电子器件的微波辅助翻转和自旋泵浦现象。前者将能够开发出高密度的计算机硬盘,而后者,结合直接电子检测技术,将能够实现小型化的无源微波探测器。

Spin Dynamics in Spintronic Devices: A Growing Science in Microwave Applications

The spintronics refers to the research area where electron spins, in additional to or sometimes in place of electron charges, are controlled and manipulated to give rise to an array of properties. Spintronic devices have already found applications in computer hard drive and magnetic random access memory, profoundly changed the information technology industry. These applications utilize the spin polarized transport where electron with fixed spin direction transverse through magnetic heterostructures. More recently, investigation of spin dynamics in spintronic device relates microwave with spin polarized transport, offering significant potential for novel microwave devices with dimension far less than the microwave wavelength. In this “review-like” article, we first briefly introduce the concept of spintronic devices. Microwave experiments with spintronic devices are discussed next in the context of microwave assisted switching and spin pumping phenomenon. The former has potential for developing high density computer hard disk, the latter, with the development of direct electronic detection, could lead to miniaturized and passive microwave detector.