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Ab Initio Theory of Perpendicular Transport in Metallic Magnetic Multilayers

  • Josef Kudrnovský
  • Václav Drchal
  • Claudia Blaas
  • Peter Weinberger
  • Ilja Turek
  • Patrick Bruno

Abstract

The current-perpendicular-to-plane (CPP) magnetoconductance of a sample sandwiched by two ideal non-magnetic leads is described at an ab initio level. The socalled ‘active’ part of the system is a trilayer consisting of two magnetic slabs of finite thickness separated by a non-magnetic spacer. We use a transmission matrix formulation of the conductance based on surface Green functions as formulated by means of the tight-binding linear muffin-tin orbital method. An equivalent and computationally more efficient formulation of the problem based on reflection matrices is also presented. The formalism is extended to the case of lateral supercells with random arrangements of atoms which in turn allows to deal with ballistic and diffusive transport on equal footing. Applications refer to fcc-based Co/Cu/Co(001) trilayers.

Keywords

Giant Magnetoresistance Coherent Potential Approximation Space Thickness Empty Symbol Spacer Layer Thickness 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. [1]
    M.N. Baibich, J.M. Broto, A. Fert, F. Nguyen Van Dau, F. Petroff, P. Etienne, G. Creuzet, A. Friedrich, and J. Chazelas, Giant Magnetoresistance of (001)Fe/(001) Cr Magnetic Superlattices Phys. Rev. Lett. 61, 2472 (1988)ADSCrossRefGoogle Scholar
  2. G. Binasch, P. Grünberg, F. Saurenbach, and W. Zinn, Enhanced Magnetoresistance in Layered Magnetic-Structures With Antiferromagnetic Interlayer Exchange Phys. Rev. B 39, 4828 (1989).ADSCrossRefGoogle Scholar
  3. [2]
    W.P. Pratt Jr., S.-F. Lee, J.M. Slaughter, R. Loloee, P.A. Schroeder, and J. Bass, Perpendicular Giant Magnetoresistances of Ag/Co Multilayers Phys. Rev. Lett. 66, 3060 (1991).ADSCrossRefGoogle Scholar
  4. [3]
    P.M. Levy, Solid State Phys. 47, 367 (1994).CrossRefGoogle Scholar
  5. [4]
    K.M. Schep, P.J. Kelly, and G.E.W. Bauer, Ballistic transport and electronic structure Phys. Rev. B 57, 8907 (1998).ADSGoogle Scholar
  6. [5]
    M.A.M. Gijs and G.E.W. Bauer, Perpendicular giant magnetoresistance of magnetic multilayers Adv. Phys. 46, 285 (1997).ADSCrossRefGoogle Scholar
  7. [6]
    P. Zahn, I. Mertig, M. Richter, and H. Eschrig, Ab-Initio Calculations of the Giant Magnetoresistance Phys. Rev. Lett. 75, 3216 (1995).CrossRefGoogle Scholar
  8. [7]
    D.R. Penn and M.D. Stiles, Solution of the Boltzmann equation without the relaxation-time approximation Phys. Rev. B 59, 13338 (1999).ADSCrossRefGoogle Scholar
  9. [8]
    W.H. Butler, X.-G. Zhang, D.M.C. Nicholson, and J.M. Mac Laren, First-Principles Calculations of Electrical-Conductivity and Giant Magnetoresistance of Co-Vertical-Bar-Cu-Vertical-Bar-Co Spin Valves Phys. Rev. B 52, 13399 (1995).Google Scholar
  10. [9]
    P. Weinberger, P.M. Levy, J. Banhart, L. Szunyogh, and B. Ûjfalussy, ’Band structure’ and electrical conductivity of disordered layered systems J. Phys.: Condens. Matter 8, 7677 (1996)ADSCrossRefGoogle Scholar
  11. C. Blaas, P. Weinberger, L. Szunyogh, P.M. Levy, and C.B. Sommers, Ab initio calculations of magnetotransport for magnetic multilayers Phys. Rev. B 60, 492 (1999).ADSGoogle Scholar
  12. [10]
    S. Datta, Electronic Transport in Mesoscopic Systems (Cambridge University Press, Cambridge, 1995).Google Scholar
  13. [11]
    I. Turek, V. Drchal, J. Kudrnovský, M. Sob, and P. Weinberger, Electronic Structure of Disordered Alloys, Surfaces and Interfaces (Kluwer, Boston-London-Dordrecht, 1997).CrossRefGoogle Scholar
  14. [12]
    V. Drchal, J. Kudrnovský, and I. Turek, Ab-initio calculations of the electronic and atomic structure of solids and their surfaces Comput. Phys. Commun. 97, 111 (1996).ADSCrossRefGoogle Scholar
  15. [13]
    J.A. Stovneng and P. Lipavský, Multiband Tight-Binding Approach to Tunneling in Semiconductor Heterostructures - Application to Gamma-X Transfer in GaAs Phys. Rev. B 49, 16494 (1994).ADSCrossRefGoogle Scholar
  16. [14]
    J. Mathon, A. Umerski, and M. Villeret, Oscillations with Co and Cu thickness of the current- perpendicular-to-plane giant magnetoresistance of a Co/Cu/Co(001) trilayer Phys. Rev. B 55, 14378 (1997).ADSCrossRefGoogle Scholar
  17. [15]
    J. Cerdá, M.A. Van Hove, P. Sautet, and M. Salmeron, Efficient method for the simulation of STM images. I. Generalized Green-function formalism Phys. Rev. B 56, 15885 (1997).Google Scholar
  18. [16]
    S. Sanvito, C.J. Lambert, J.H. Jefferson, and A.M. Bratkovsky, General Green’s-function formalism for transport calculations with spd Hamiltonians and giant magnetoresistance in Co- and Ni-based magnetic multilayers Phys. Rev. B 59, 11936 (1999).Google Scholar
  19. [17]
    P. Bruno, H. Itoh, J. Inoue, and S. Nonoyama, Influence of disorder on the perpendicular magnetoresistance of magnetic multilayers J. Mag. Mag. Mat. 198–199, 46 (1999).CrossRefGoogle Scholar
  20. [18]
    E.Yu. Tsymbal and D.G. Pettifor, Spin-polarized electron tunneling across a disordered insulator Phys. Rev. B 58, 432 (1998).ADSGoogle Scholar
  21. [19]
    F. James, A Review of Pseudorandom Number Generators Comput. Phys. Commun. 60, 329 (1990).ADSzbMATHCrossRefGoogle Scholar
  22. [20]
    S. Zhang and P. Levy, Interplay of the specular and diffuse scattering at interfaces of magnetic multilayers Phys. Rev. B 57, 5336 (1998).ADSGoogle Scholar
  23. [21]
    V. Drchal, J. Kudrnovský, I. Turek, and P. Weinberger, Interlayer magnetic coupling: The torque method Phys. Rev. B 53, 15036 (1996).ADSCrossRefGoogle Scholar
  24. [22]
    B.L. Gyorffy and G.M. Stocks, in Electrons in Disordered Metals and at Metallic Surfaces, eds. P. Phariseau, B.L. Gyorffy, and L. Scheire (NATO ASI Series, Plenum Press, New York, 1979).Google Scholar

Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • Josef Kudrnovský
    • 1
  • Václav Drchal
    • 1
  • Claudia Blaas
    • 2
  • Peter Weinberger
    • 2
  • Ilja Turek
    • 3
  • Patrick Bruno
    • 4
  1. 1.Institute of PhysicsAcademy of Sciences of the Czech RepublicPrague 8Czech Republic
  2. 2.Center for Computational Materials ScienceTechnical University of ViennaViennaAustria
  3. 3.Institute of Physics of MaterialsAcademy of Sciences of the Czech RepublicBrnoCzech Republic
  4. 4.Max-Planck-Institut für MikrostrukturphysikHalleGermany

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