AVS 56th International Symposium & Exhibition
    Magnetic Interfaces and Nanostructures Wednesday Sessions
       Session MI+EM-WeA

Paper MI+EM-WeA11
Order From Chaos: α-Fe(001)/GaAs(001)

Wednesday, November 11, 2009, 5:20 pm, Room C1

Session: Magnetism and Spin Injection in Semiconductors
Presenter: J.G. Tobin, Lawrence Livermore National Laboratory
Authors: J.G. Tobin, Lawrence Livermore National Laboratory
S.W. Yu, Lawrence Livermore National Laboratory
S.A. Morton, Lawrence Berkeley National Laboratory
G.D. Waddill, Missouri University of Science and Technology
J.D.W. Thompson, University of Salford, UK
J.R. Neal, University of Salford, UK
M. Spangenburg, University of Salford, UK
T.H. Shen, University of Salford, UK
Correspondent: Click to Email
For many years, the technological possibilities of spintronic or magneto-electronic devices [1], particularly when coupled with potentially pure spin sources such as half-metallic ferro-magnets, [2] have engendered great interest.  Despite the limitations encountered in such potential sources [3], there is still ample reason to pursue such concepts.  This is because, in part, even with sources that operate below 100% polarization, technologically important devices should emerge. [1] However, the challenges of device integration remain significant even for cases with lowered expectations, because often the physical realities of intermixing, disorder and alloying can creep into the attempts to fabricate structures based upon ideal conceptual designs.  Within this context, ferromagnetic-semiconductor interfaces are potentially important for the future applications of spintronic devices.  One possibility for a room temperature spin injector is Fe/GaAs. 
The growth of Fe upon GaAs(001) has been studied with Photoelectron Spectroscopy (PES), including Spin-Resolved PES .  Despite evidence of atomic level disorder such as intermixing, [4] an over-layer with the spectroscopic signature of α-Fe(001), with a bcc real space ordering, is obtained.  The results will be discussed in light of the possibility of using such films as a spin polarized source in device applications.
Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344. Work that was performed by UMR personnel was supported in part by the Office of Basic Energy Science at the U.S Department of Energy.  Work that was performed by LLNL personnel was supported in part by the Office of Basic Energy Science at the U.S Department of Energy and Campaign 2 of WCI at LLNL.  We would also like to thank  J.A.D. Matthew, D. Greig, A.E.R. Malins, E.A. Seddon, and M. Hopkinson for their help with this project.
References
1.    G.A. Prinz, Science 282, 1660 (1998).
2.    R.A. de Groot, F.M. Mueller, P.G. van Engen and K.H.J. Buschow, Phys. Rev. Lett. 50, 2024 (1983).
3.    P. Dowben, J. Phys. Condensed Matter 19, 310301 (2007).
4.    J.D.W. Thompson, J.R. Neal, T.H. Shen, S.A. Morton, J.G. Tobin, G.D. Waddill, J.A.D. Matthew, D. Greig, and M. Hopkinson, J. Appl. Phys. 104, 024516 (2008) and references therein.