SPIN-POLARIZED ELECTRON-MICROSCOPY
SPIN-POLARIZED ELECTRON-MICROSCOPY
复制标题
DOI：
10.1088/0031-8949/38/2/035
复制
发表时间：
1988-08-01
期刊：
影响因子：
2.9
通讯作者：
PIERCE, DT
中科院分区：
文献类型：
--
作者：
PIERCE, DT
当前磁性技术面临的一个具有许多影响的科学挑战是以尽可能高的空间分辨率对磁性微结构进行成像，以便观察磁畴甚至磁畴壁内的自旋配置。最终，人们可以设想对单个原子的磁矩进行成像，这也使得观察反铁磁结构成为可能。提出了通过精细聚焦（非偏振）扫描电子显微镜（SEM）光束产生的二次电子的自旋极化测量，以获得高分辨率磁化图像。另一种测量方法是在 SEM 中使用自旋偏振入射光束，但存在许多困难，对此进行了讨论。为了以更高的空间分辨率测量自旋构型，考虑在扫描场发射和隧道显微镜中引入电子自旋极化的可能性。由专门制备的单原子扫描场发射尖端产生的二次电子的自旋极化的测量看起来很有前景。如果尖端本身是自旋极化电子源，则扫描隧道显微镜中自旋构型的高分辨率成像似乎是可能的。描述了使用铁磁尖端或光泵浦半导体尖端所涉及的潜在优点和未解决的问题。
A current scientific challenge with many ramifications for magnetic technology is to image magnetic microstructure with the highest possible spatial resolution in order to observe magnetic domains or even spin configurations within a domain wall. Ultimately one can envision imaging the magnetic moment of individual atoms which would also make possible the observation of antiferromagnetic structures. The measurement of the spin polarization of secondary electrons generated by a finely focussed (unpolarized) scanning electron microscope (SEM) beam to obtain high-resolution magnetization images is presented. An alternative measurement, using a spin-polarized incident beam in an SEM, has many difficulties which are discussed. To measure spin configurations with higher spatial resolution, the possibility of introducing electron spin polarization in scanning field-emission and tunneling microscopy is considered. The measurement of the spin polarization of secondary electrons generated by a specially prepared single-atom scanning field-emission tip looks promising. High-resolution imaging of spin configurations in scanning tunneling microscopy appears possible if the tip itself is a source of spin-polarized electrons. The potential advantages and unsolved problems involved in using a ferromagnetic tip or an optically pumped semiconductor tip are described.