Unidirectional Anisotropy in Mangaite Based Ferromagnetic-Antiferromagnetic Multilayers

摘要

In mixed valence manganites a large negative magnetoresistance (MR), termed colossal magnetoresistance [1] (CMR), can be obtained due to a metal-insulator transition at the ferromagnetic Curie point [2]. However little progress has been made towards using these materials in applications, mainly due to the strong temperature dependence of the CMR effect and the large saturation fields (of the order of Tesla) required. Tunneling and grain boundary effects [3-8] as well as itnerface scattering [9] seem promising towards getting useful MR in these materials. In particular the high degree of spin polarization [10] makes these materials promising for spin-electronic device applications.