GOALI: NanoEngineering of Magnetic Interfaces for SpinElectronics

University Of Connecticut, Storrs CT

Investigators

Abstract

Spin electronics is quickly becoming one of the new frontiers of 21st century electronics. The central theme of this new technology is spin dependent transport. One of the major current efforts is the development of materials with very high (100%) degree of spin polarization for high performance spin-electronics devices. Although a significant progress has been recently made in showing that some transition metal oxides and some Hoysler alloys do exhibit a high degree of spin polarization, the use of such material in room temperature spin-electronics devices like magnetic tunneling junction (MTJ) have yielded disappointing small effects. These results have reinforced the idea that the performance of such devices is critically dependent on the spin-polarization at the interfaces rather than in the bulk phase of these materials. Intellectual merit: We propose to launch a concentrated effort to understand and to nanoengineer the magnetic interfaces for spin electronics application though a GOALI collaboration between University of Connecticut (UConn) and IBM. In particular we propose to directly measure the electron spin polarization of electrons at the Fermi level by spin resolved photoemission technique. The interface properties will be accessed by growth of ultra-thin oxide and other tunneling barrier materials on top of the relevant ferromagnetic films, which will be facilitated by short photoelectron escape depth, being on the order of the barrier thickness. We propose to lunch a systematic study of such structures fabricated mainly by S. S. P. Parkin (IBM/Almaden) and Scott Chambers (PNNL). The spin-resolved experiments will be performed PI's laboratory at UConn as well as at the U5UA beamline of the National Synchrotron Light Source (NSLS). Combination of PI's expertise in spin-resolved photoemission with the expertise of participating laboratory in films synthesis will provide unique synergy for the proposed task. The program is expected to make significant contribution to understanding and nanoengineering of optimum interfaces for MTJ application. Previous successful collaboration between PI and Co-PI (S.S.P. Parkin) should aid in strong interaction between the university and the industrial partner in this GOALI project. Broader impact: This program will contribute to the future progress of the emerging spin-electronic technology by providing invaluable information on the spin polarization at relevant magnetic interfaces. Close collaboration between the university (UConn), the industry (IBM) and the national labs (PNNL and NSLS) will provide an excellent setting for education and training of graduate students in cutting-edge technology. In particular, close ties with IBM though this GOALI initiative will provide students with first-hand experience on the development of novel electronic technologies . The outreach will include participation of undergraduate students in summer research projects supported through NSF-funded REU program at UConn. Live lab demonstrations and tutorials will be given to groups of K-12 students during organized visits to UConn. The local K-12 science teachers already participating in workshops at UConn. will be given tutorials of how the proposed research impacts the development of new technologies.