Spin wave excitation by spin-polarized electric current in all-metallic and tunnel magnetic junctions

全金属和隧道磁结中自旋极化电流的自旋波激发

• 批准号: 5374533
• 负责人: Professor Dr. Sergej O. Demokritov, Ph.D.
• 金额: --
• 依托单位: Institut für Angewandte Physik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2002
• 资助国家: 德国
• 起止时间: 2001-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5374533?language=en
• 关键词: Spin; wave; excitation; spin; polarized

Current induced magnetic switching describing the change in the direction of magnetization of a magnetic film due to interaction of spin-polarized conduction electrons with the film's magnetic moments is considered now as a potential switching mechanism for next generations of magnetic memory. This interaction, however, should also lead to the amplification of non-uniform excitations. The subject of the project is to investigate the process of spin wave excitation and amplification caused by the spin polarized current. The experiment will be realized in metallic magnetic layered systems with anti ferromagnetic interlayer coupling: spin waves will be excited by an ac current of microwave frequency in a specially designed MW cavity allowing for a spatial separation of electric and magnetic fields. Thus, the parasitic effect of spin wave excitation by the MW magnetic field, unavoidable in point contact experiments, will be excluded. A spatial modulation of the spin polarized current will generate spin waves of well defined wave vector. Using short pulses of electric current and time resolved Brillouin light scattering spectroscopy the dynamics of the excitation process will be studied. Changing the time delay between the current pulse and the time moment of the spin wave detection, the growth of the spin wave intensity due to interaction with the current pulse and their consequent decay will be investigated.

描述由于自旋极化传导电子与膜的磁矩的相互作用而导致的磁性膜的磁化方向的变化的电流感生磁切换现在被认为是下一代磁存储器的潜在切换机制。然而，这种相互作用也会导致非均匀激励的放大。本计画的主要目的是探讨自旋极化电流所引起的自旋波激发与放大的过程。该实验将在具有反铁磁层间耦合的金属磁性分层系统中实现：自旋波将在一个专门设计的MW腔中由微波频率的交流电流激发，允许电场和磁场的空间分离。因此，由MW磁场的自旋波激发的寄生效应，在点接触实验中不可避免的，将被排除。自旋极化电流的空间调制将产生具有明确定义的波矢量的自旋波。使用短脉冲电流和时间分辨布里渊光散射光谱的激发过程的动力学将进行研究。改变电流脉冲和自旋波检测时刻之间的时间延迟，将研究由于与电流脉冲的相互作用而导致的自旋波强度的增长及其随之而来的衰减。