Jedema F J, Filip A T, van Wees B J
Department of Applied Physics and Materials Science Centre, University of Groningen, The Netherlands.
Nature. 2001 Mar 15;410(6826):345-8. doi: 10.1038/35066533.
Finding a means to generate, control and use spin-polarized currents represents an important challenge for spin-based electronics, or 'spintronics'. Spin currents and the associated phenomenon of spin accumulation can be realized by driving a current from a ferromagnetic electrode into a non-magnetic metal or semiconductor. This was first demonstrated over 15 years ago in a spin injection experiment on a single crystal aluminium bar at temperatures below 77 K. Recent experiments have demonstrated successful optical detection of spin injection in semiconductors, using either optical injection by circularly polarized light or electrical injection from a magnetic semiconductor. However, it has not been possible to achieve fully electrical spin injection and detection at room temperature. Here we report room-temperature electrical injection and detection of spin currents and observe spin accumulation in an all-metal lateral mesoscopic spin valve, where ferromagnetic electrodes are used to drive a spin-polarized current into crossed copper strips. We anticipate that larger signals should be obtainable by optimizing the choice of materials and device geometry.
找到一种产生、控制和利用自旋极化电流的方法，是自旋电子学（或称“自旋电子技术”）面临的一项重大挑战。通过将电流从铁磁电极驱动到非磁性金属或半导体中，可以实现自旋电流以及相关的自旋积累现象。这在15年多以前首次在低于77K的温度下对单晶铝棒进行的自旋注入实验中得到证实。最近的实验已经证明，利用圆偏振光的光注入或磁性半导体的电注入，可以成功地对半导体中的自旋注入进行光学检测。然而，在室温下实现完全的电自旋注入和检测一直未能成功。在此，我们报告在室温下对自旋电流进行电注入和检测，并在一种全金属横向介观自旋阀中观察到自旋积累，其中铁磁电极用于将自旋极化电流驱动到交叉的铜条中。我们预计，通过优化材料选择和器件几何结构，应该可以获得更大的信号。
