Abstract
Spin-dependent transport of relativistic electrons through graphene based double barrier (well) structures with ferromagnetic electrodes have been theoretically investigated. Electron transmission with different spin states is strongly influenced by the incident wave vector, the height (depth) of the barrier and the separation between them. When the angle of the incident electrons is varied from zero to ±π/2, spin polarization varies from zero to 100% with characteristic oscillations that indicate spin anisotropy. Due to Klein tunnelling, spin-polarization is always zero for normal incident electrons; high spin-polarization only occurs at large incident angles. Because the resonance features in the spin-dependent transmission result from resonant electron states in wells or hole states in barriers, the conductance can reach e2/h in this resonant-tunnelling structure.
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K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S.V. Dubonos, I.V. Grigorieva, A.A. Firsov, Science 306, 666 (2004)
J. Tworzydlo, B. Trauzettel, M. Titov, A. Rycerz, C.W.J. Beenakker, Phys. Rev. Lett. 96, 246802 (2006)
K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, M.I. Katsnelson, I.V. Grigorieva, S.V. Dubonos, A.A. Firsov, Nature 438, 197 (2005); K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, M.I. Katsnelson, I.V. Grigorieva, S.V. Dubonos, A.A. Firsov, Nature Phys. 2, 177 (2006)
Y. Zhang, Y.W. Tan, H.L. Stormer, P. Kim, Nature 438, 201 (2005)
V.P. Gusynin, S.G. Sharapov, Phys. Rev. Lett. 95, 146801 (2005)
E. McCann, V. Falko, Phys. Rev. Lett. 96, 086805 (2006)
O. Klein, Z. Phys. 53, 157 (1929)
M.I. Katsnelson, K.S. Novoselov, A.K. Geim, Nat. Phys. 2, 620 (2006)
R.K. Su, G.C. Siu, X. Chou, J. Phys. A 26, 1001 (1993)
N. Dombey, A. Calogeracos, Phys. Rep. 315, 41 (1999)
M.J. Pereira Jr., V. Mlinar, F.M. Peeters, P. Vasilopoulos, Phys. Rev. B 74, 045424 (2006)
M.A.H. Vozmediano, M.P. López-Sancho, T. Stauber, F. Guinea, Phys. Rev. B 72, 155121 (2005)
Y.W. Son, M.L. Cohen, S.G. Louie, Nature 444, 347 (2006)
N. Tombros, C. Jozsa, M. Popinciuc, B.J. van Wees, Nature 448, 571 (2007)
C.X. Bai, Y. Yang, X. Zhang, Appl. Phys. Lett. 92, 102513 (2008)
H. Haugen, D. Huertas-Hernando, A. Brataas, Phys. Tev. B 77, 115406 (2008)
S.A. Wolf, D.D. Awschalom, R.A. Buhrman, J.M. Daughton, S. von Molnr, M.L. Roukes, A.Y. Chtchelkanova, D.M. Treger, Science 294, 1488 (2001)
M. Büttiker, Y. Imry, R. Landauer, S. Pinhas, Phys. Rev. B 31, 6207 (1985)
R. Landauer, Philos. Mag. 21, 863 (1970)
C.X. Bai, X.D. Zhang, Phys. Lett. A 372, 725 (2008)
S.T. Chui, Phys. Rev. B 55, 5600 (1997)
A. Geim, (unpublished)
L. Brey, H.A. Fertig, Phys. Rev. B 76, 205435 (2007)
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Li, YX. Spin-polarization and magnetoresistance in graphene-based resonant-tunnelling structures. Eur. Phys. J. B 68, 119–122 (2009). https://doi.org/10.1140/epjb/e2009-00085-7
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DOI: https://doi.org/10.1140/epjb/e2009-00085-7