Physics of the Solid State

, Volume 48, Issue 3, pp 432–440 | Cite as

Spin polarization of charge carriers and Andreev reflection in (LaCa)MnO/superconductor point contacts

  • A. I. D’yachenko
  • V. A. D’yachenko
  • V. Yu. Tarenkov
  • V. N. Krivoruchko
Metals and Superconductors


Spin polarization of charge carriers in La0.65Ca0.35MnO3 (LCMO) is studied using point-contact Andreev spectroscopy. Pb and MgB2 are used to make superconducting electrodes. In all cases, the transport spin polarization obtained from the conductivity of LCMO/superconductor point contacts does not exceed 80–85%. Different models of the current flow through the superconductor-ferromagnetic metal contact and possible reasons for noncomplete spin polarization of a current in manganites are explored. The level of spin polarization observed in Sharvin contacts (contact area ∼104 Å2) is most naturally explained in terms of a model that suggests separation of the crystal into nanosized magnetic phases, only one of which is a ferromagnetic metal with full spin polarization of charge carriers.

PACS numbers

74.45.+c 74.50.+r 74.81.-g 


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  1. 1.
    A. V. Vedyaev, Usp. Fiz. Nauk 172(12), 1458 (2002) [Phys. Usp. 45 (12), 1296 (2002)].Google Scholar
  2. 2.
    V. Yu. Irkhin and M. I. Katsnel’son, Usp. Fiz. Nauk 164(7), 705 (1994) [Phys. Usp. 37 (7), 659 (1994)]; V. Yu. Irkhin, M. I. Katsnelson, and A. I. Lichtenstein, condmat/0406487.Google Scholar
  3. 3.
    M. B. Salamon and M. Jaime, Rev. Mod. Phys. 73(3), 583 (2001).CrossRefADSGoogle Scholar
  4. 4.
    E. Dagotto, Nanoscale Phase Separation and Colossal Magnetoresistance (Springer, Berlin, 2002).Google Scholar
  5. 5.
    Y. Ji, C. L. Chein, Y. Tomioka, and Y. Tokura, Phys. Rev. B: Condens. Matter 66(1), 012 410 (2002).Google Scholar
  6. 6.
    S. W. Han, J.-S. Kang, K. H. Kim, J. D. Lee, J. H. Kim, S. C. Wi, C. Mitra, P. Raychaudhuri, S. Wirth, K. J. Kim, B. S. Kim, J. I. Jeong, S. K. Kwon, and B. I. Min, Phys. Rev. B: Condens. Matter 69(10), 104 406 (2004).Google Scholar
  7. 7.
    E. L. Nagaev, Phys. Rep. 346(6), 387 (2001).CrossRefADSGoogle Scholar
  8. 8.
    Moon-Ho Jo, N. D. Mathur, N. K. Todd, and M. G. Blamire, Phys. Rev. B: Condens. Matter 61(22), 14 905 (2000).Google Scholar
  9. 9.
    J. Y. T. Wei, N.-C. Yeh, and R. P. Vasquez, Phys. Rev. Lett. 79(25), 5150 (1997).CrossRefADSGoogle Scholar
  10. 10.
    R. J. Soulen, Jr., J. M. Byers, M. S. Osofsky, B. Nadgorny, T. Ambrose, S. F. Cheng, P. R. Broussard, C. T. Tanaka, J. Nowak, J. S. Moodera, A. Barry, and J. M. D. Coey, Science (Washington) 282(1), 85 (1998).ADSGoogle Scholar
  11. 11.
    I. I. Mazin, A. A. Golubov, and B. Nadgorny, J. Appl. Phys. 89(11), 7576 (2001).CrossRefADSGoogle Scholar
  12. 12.
    B. Nadgorny, I. I. Mazin, M. Osofsky, R. J. Soulen, Jr., P. Broussard, R. M. Stroud, D. J. Singh, V. G. Harris, A. Arsenov, and Ya. Mukovskii, Phys. Rev. B: Condens. Matter 63(18), 184 433 (2001).Google Scholar
  13. 13.
    B. P. Vodop’yanov and L. P. Tagirov, Pis’ma Zh. Éksp. Teor. Fiz. 77(3), 153 (2003) [JETP Lett. 77 (3), 126 (2003)].Google Scholar
  14. 14.
    A. F. Andreev, Zh. Éksp. Teor. Fiz. 46(5), 182 (1964) [Sov. Phys. JETP 19 (5), 130 (1964)].Google Scholar
  15. 15.
    M. M. Savosta and P. Novák, Phys. Rev. Lett. 87(13), 137 204 (2001).Google Scholar
  16. 16.
    M. Ziese, Rep. Prog. Phys. 65(1), 143 (2002).ADSGoogle Scholar
  17. 17.
    Yu. V. Sharvin, Zh. Éksp. Teor. Fiz. 48(3), 984 (1965) [Sov. Phys. JETP 21 (3), 655 (1965)].Google Scholar
  18. 18.
    G. E. Blonder, M. Tinkham, and T. M. Klapwijk, Phys. Rev. B: Condens. Matter 25(7), 4515 (1982).ADSGoogle Scholar
  19. 19.
    I. O. Kulik, A. N. Omel’yanchuk, and I. G. Kutuzov, Fiz. Nizk. Temp. (Kiev) 14(2), 149 (1988).Google Scholar
  20. 20.
    J. Mitra, A. K. Raychaudhuri, Ya. M. Mukovskii, and D. Shulyatev, Phys. Rev. B: Condens. Matter 68(13), 134 428 (2003).Google Scholar
  21. 21.
    W. E. Pickett and D. J. Singh, Phys. Rev. B: Condens. Matter 53(3), 1146 (1996).ADSGoogle Scholar
  22. 22.
    V. Yu. Tarenkov, A. I. D’yachenko, and V. N. Krivoruchko, Zh. Éksp. Teor. Fiz. 120(1), 205 (2001) [JETP 93 (1), 180 (2001)].Google Scholar
  23. 23.
    M. Edwards, Adv. Phys. 51, 1259 (2002).ADSGoogle Scholar
  24. 24.
    F. Pérez-Willard, J. C. Cuevas, C. Sürgers, P. Pfundstein, J. Kopu, M. Eschrig, and H. V. Löhneysen, Phys. Rev. B: Condens. Matter 69(14), 140502 (2004).Google Scholar
  25. 25.
    K. Xia, P. J. Kelly, G. E. W. Bauer, and I. Turek, Phys. Rev. Lett. 89(16), 166603 (2002).Google Scholar
  26. 26.
    C. H. Kant, O. Kurnosikov, A. T. Filip, P. LeClair, H. J. M. Swagten, and W. J. M. de Jonge, Phys. Rev. B: Condens. Matter 66(21), 212403 (2002).Google Scholar
  27. 27.
    M. Jaime, P. Lin, M. B. Salamon, and P. D. Han, Phys. Rev. B: Condens. Matter 58(10), 5901 (1998).ADSGoogle Scholar
  28. 28.
    S. Satpathy, Z. S. Popović, and F. R. Vakajlović, Phys. Rev. Lett. 76(6), 960 (1996).CrossRefADSGoogle Scholar
  29. 29.
    J.-H. Park, E. Vescovo, H.-J. Kim, C. Kwon, R. Ramesh, and T. Venkatesan, Phys. Rev. Lett. 81(9), 1953 (1998).CrossRefADSGoogle Scholar
  30. 30.
    R. Bertacco, M. Portalupi, M. Marcon, L. Duó, F. Ciccacci, M. Bowen, J. P. Contour, and A. Barthélemy, J. Magn. Magn. Mater. 242–245 part 2, 710 (2002).Google Scholar
  31. 31.
    M. Fäth, S. Freisem, A. A. Menovsky, Y. Tomioka, J. Aarts, and J. A. Mydosh, Science (Washington) 285(5433), 1540 (1999).Google Scholar
  32. 32.
    M. Uehara, S. Mori, C. H. Chen, and S.-W. Cheong, Nature (London) 399(6736), 560 (1999).ADSGoogle Scholar
  33. 33.
    M. M. Savosta, V. N. Krivoruchenko, I. A. Danilenko, V. Yu. Tarenkov, T. E. Konstantinova, A. V. Borodin, and V. V. Varyukhin, Phys. Rev. B: Condens. Matter 69(2), 024 413 (2004).Google Scholar
  34. 34.
    V. Chechersky, A. Nath, C. Michel, M. Hervieu, K. Chosh, and R. I. Greene, Phys. Rev. B: Condens. Matter 62(9), 5316 (2000).ADSGoogle Scholar
  35. 35.
    R. H. Heffner, J. E. Sonier, D. E. MacLaughlin, G. J. Niewenhuys, G. M. Luke, Y. J. Uemura, W. Ratcliff II, S.-W. Cheong, and G. Balakrishnan, Phys. Rev. B: Condens. Matter 63(9), 094 408 (2001).Google Scholar
  36. 36.
    V. L. Aksenov, A. M. Balagurov, and V. Yu. Pomyakushkin, Usp. Fiz. Nauk 173(8), 883 (2003) [Phys. Usp. 46, 911 (2003)].Google Scholar
  37. 37.
    A. Filippetti and W. E. Pickett, cond-mat/0001373 (2000).Google Scholar

Copyright information

© Pleiades Publishing, Inc. 2006

Authors and Affiliations

  • A. I. D’yachenko
    • 1
  • V. A. D’yachenko
    • 1
  • V. Yu. Tarenkov
    • 1
  • V. N. Krivoruchko
    • 1
  1. 1.Donetsk Physicotechnical InstituteNational Academy of Sciences of UkraineDonetskUkraine

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