Spin dynamics in magnetic nanostructures

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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.