Spin dynamics in magnetic nanostructures

21世纪材料科学的主要进展将以控制纳米结构的杂化和复合体系为基础。在磁学中，这条道路始于八十年代早期。超高压制造复杂的非均相磁性多层结构和超晶格使人们能够创造独特的磁性材料。这一领域的成功发生得非常快，并导致了新的和革命性的设备应用。电子的自旋而不是其电荷在电子学中创造了非凡的机会，即自旋电子学。事实上，2007年的诺贝尔奖是授予彼得·格伦伯格和阿尔伯特·费特发现巨磁电阻（GMR）的。为了继续在这一领域的快速发展，需要在纳米几何结构中对自旋相互作用的理解上取得进展。我使用分子束外延（MBE）沉积超薄膜和超晶格。采用射频、穆斯堡尔、直流和皮秒时间分辨磁光、电子输运技术和电子显微镜技术来识别磁和自旋相关的电子输运性质。我们的研究涉及自旋动力学，重点是自旋电流的研究。铁磁-隧穿结-正常金属界面处的强电子相关效应可使自旋泵浦增加十倍。在这一点上，人们可以开始考虑发展基于纯自旋电流的信息处理，这种电流不伴随着电荷的净流动。我们将开发一种使用高功率自旋电流的自旋电池。我们将测试并优化铁磁性金属和半导体之间的自旋注入，从而有机会开发出高效的自旋晶体管。这项工作将由SFU、UBC、埃德蒙顿大学、麦吉尔大学、马克斯-普朗克哈雷研究所、雷根斯堡大学和特拉华大学的科学家共同完成，这使我们能够在半导体、结构科学、磁光学、设备制造和计算机模拟方面获得广泛的专业知识。与UBC， TRIUMF，埃德蒙顿大学和麦吉尔大学的合作是加拿大高级研究所（CIFAR）计划的一部分。

The main advances in materials science in the 21st century are going to be based on controlling nanostructured hybrid and composite systems. In magnetism this path started in the early eighties. UHV fabrication of complex heterogeneous magnetic multilayer structures and superlattices has allowed one to create unique magnetic materials. The success in this field has occurred very quickly and has led to new and revolutionary device applications. The spin of the electron rather than its charge has created remarkable opportunities in electronics, coined spintronics. In fact the Nobel Prize for 2007 was awarded for the discovery of Giant Magnetoresistance (GMR) by Peter Gruenberg and Albert Fert. To continue the rapid progress in this field requires advances in the understanding of spin interactions in nanoscopic geometries. I use Molecular Beam Epitaxy (MBE) for the deposition of ultrathin films and superlattices. Radio frequency, Mossbauer, dc and pico second time resolved magneto-optical, electron transport techniques and electron microscope techniques are employed to identify magnetic and spin dependent electron transport properties. Our studies involve spin dynamics with emphasis on the study of spin currents. Strong electron correlation effects at the ferromagnet-tunneling junction-normal metal interfaces can enhance spin pumping by a factor of ten. At this point one can start to think about developing information processing based on pure spin currents which are not accompanied by the net flow of electric charge. We are going to develop a spin battery using high power spin currents. We will test and optimize the spin injection between ferromagnetic metals and semiconductors giving us an opportunity to develop an efficient spin-transistor. This work will be done in a collaborative effort involving scientists at SFU, UBC, U. Edmonton, McGill U., Max-Planck Institute Halle, U. Regensburg, and U. Delaware allowing us to cover a wide range of expertise in semiconductors, structural science, magneto-optics, device fabrication, and computer simulations. The cooperation with UBC, TRIUMF, U. Edmonton, and McGill U. are a part of Canadian Institute For Advanced Research (CIFAR) program.