The European Physical Journal B

, Volume 59, Issue 4, pp 471–474 | Cite as

Spin torque transfer structure with new spin switching configurations

  • J.-P. WangEmail author
  • H. Meng
Topical Issue on New Trends in Spin Transfer Physics


Spin torque transfer structures with new spin switching configurations are proposed, fabricated and investigated in this paper. The non-uniform current-induced magnetization switching is implemented based on both GMR and MTJ nano devices. The proposed new spin transfer structure has a hybrid free layer that consists of a layer with conductive channels (magnetic) and non-conductive matrix (non-magnetic) and traditional free layer(s). Two mechanisms, a higher local current density by nano-current-channels and a non-uniform magnetization switching (reversal domain nucleation and growth) by a magnetic nanocomposite structure, contribute in reducing the switching current density. The critical switching current density for the new spin transfer structure is reduced to one third of the typical value for the normal structure. It can be expected to have one order of magnitude or more reduction for the critical current density if the optimization of materials and fabrication processes could be done further. Meanwhile, the thermal stability of this new spin transfer structure is not degraded, which may solve the long-standing scaling problem for magnetic random access memory (MRAM). This spin transfer structure, with the proposed and demonstrated new spin switching configurations, not only provides a solid approach for the practical application of spin transfer devices but also forms a unique platform for researchers to explore the non-uniform current-induced switching process.


72.25.-b Spin polarized transport 72.25.Ba Spin polarized transport in metals 73.63.-b Electronic transport in nanoscale materials and structures 75.47.-m Magnetotransport phenomena; materials for magnetotransport 


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  1. J.C. Slonczewski, J. Magn. Magn. Mater. 159, L1 (1996) Google Scholar
  2. L. Berger, Phys. Rev. B 54, 9353, (1996) CrossRefADSGoogle Scholar
  3. J.A. Katine, F.J. Albert, E.B. Myers, D.C. Ralph, R.A. Buhrman, Phys. Rev. Lett. 84, 3149 (2000) CrossRefADSGoogle Scholar
  4. F.J. Albert, J.A. Katine, R.A. Buhrman, D.C. Ralph, Appl. Phys. Lett. 77, 3809 (2000) CrossRefADSGoogle Scholar
  5. Y. Jiang, S. Abe, T. Ochiai, T. Nozaki, A. Hirohata, N. Tezuka, K. Inomata, Phys. Rev. Lett. 92, 167204 (2004) CrossRefADSGoogle Scholar
  6. J. Grollier, V. Gros, A. Hamzic, J.M. George, H. Jaffes, A. Fert, G. Faini, J. Ben Youssef, H. Le Gall, Appl. Phys. Lett. 78, 3663 (2001) CrossRefADSGoogle Scholar
  7. G.D. Fuchs, N.C. Emley, I.N. Krivorotov, P.M. Braganca, E.M. Ryan, S.I. Kiselev, J.C. Sankey, D.C. Ralph, R.A. Buhrman, Appl. Phys. Lett. 85, 1205 (2004) CrossRefADSGoogle Scholar
  8. J.Z. Sun, J. Magn. Magn. Mater. 202, 157 (1999) CrossRefADSGoogle Scholar
  9. R.H. Koch, J.A. Katine, J.Z. Sun, Phys. Rev. Lett. 92, 088302 (2004) CrossRefADSGoogle Scholar
  10. H. Kurt, R. Loloee, W.P. Pratt, J. Bass, J. Appl. Phys. 97, 10C706 (2005) CrossRefGoogle Scholar
  11. H. Oshima et al., IEEE Tran. Magn. 39(5), 2377 (2003) Google Scholar
  12. H. Meng, J.P. Wang, IEEE Trans. Mag. 41, 2612 (2005) CrossRefGoogle Scholar
  13. J.P. Wang, W. Shen, J. Bai, R.H. Victora, J.H. Judy, W.L. Song, Appl. Phys. Lett. 86, 142504 (2005) CrossRefADSGoogle Scholar
  14. W. Shen, J. Bai, R.H. Victora, J.H. Judy, J.P. Wang, J. Appl. Phys. 97, 10N513 (2005) Google Scholar
  15. J.P. Wang, W. Shen, J. Bai, IEEE Trans. Magn. 41, 3181 (2005) CrossRefGoogle Scholar
  16. H. Oshima, K. Nagasaka, Y. Seyama, A. Jogo, Y. Shimizu, A. Tanaka, Y. Miura, IEEE Trans. Magn. 39, 2377 (2003) CrossRefGoogle Scholar
  17. A. Tanaka, Y. Seyama, A. Jogo, H. Oshima, R. Kondo, H. Kishi, C. Kamata, Y. Shimizu, S. Eguchi, K. Satoh, IEEE Tran. Magn. 40, 203 (2004) CrossRefGoogle Scholar
  18. H. Meng, J.P. Wang, Appl. Phys. Lett. 88, 172506 (2006) CrossRefADSGoogle Scholar
  19. J. Manschot, A. Brataas, G.E.W. Bauer, Phys. Rev. Lett. 69, 092407 (2004) Google Scholar
  20. J. Xiao, A. Zangwill, M.D. Stiles, Phys. Rev. B 70, 172405 (2004) CrossRefADSGoogle Scholar

Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2007

Authors and Affiliations

  1. 1.The Center for Micromagnetics and Information Technologies (MINT) & Department of Electrical & Computer EngineeringUniversity of MinnesotaMinneapolisUSA

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