Symposium Q: Magnetoelectronics - Novel Magnetic Phenomena in Nanostructures

摘要

The area of anisotropic magnetotransport in magnetic superlattices remains controversial and intensely investigated by theorists and experimentalists, as demonstrated in Symposium Q on Magnetoelectronics-Novel Magnetic Phenomena in Nanostructures. The main issues that were highlighted are the importance of mean free path, the connection between structure and GMR, and whether GMR originates from the bulk or interface in the superlattice, especially in experiments in which the current flows perpendicular to the interfaces. B.J. Hickey (Leeds Univ.) said, based on experiments in Permalloy- containing superlattices, that the mean free path is crucial in determining the GMR. Theoretical work (P. Weinberger, Univ. of Vienna) seems to show that in the Fe/Cr interface, scattering originates in the interface in agreement with experimental claims (J. Santamaria, Univ. of Madrid, Spain). The magnetic proximity effect, while an old subject, has received renewed attention from experimentalists and theorists who are principally motivated by the. developments in spintronics. M. Kiwi (Catholic Univ., Chile) summarized the long history of this field. Generally, it is accepted and found experimentally (A. Hoffmann, ANL) that the magnetic proximity effect is small and confined to a very short distance close to the interface. A novel type of proximity effect was predicted theoretically (LJ. Sham, UCSD) in which electrons in a semiconductor become polarized if reflected from an interface with a magnetic material.