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Spintronics pp 243-269 | Cite as

Hard X-Ray Photoelectron Spectroscopy of New Materials for Spintronics

  • Gerhard H. Fecher
  • Claudia Felser

Abstract

In this work, results of hard X-ray photoelectron spectroscopy (HAXPES) of Heusler compounds and new materials for spintronics are presented. The class of Heusler materials includes some interesting half-metallic and ferromagnetic properties that were predicted by theory. HAXPES allows a direct comparison of the measured and the calculated electronic structure. Valence band spectroscopy of bulk materials by HAXPES is illustrated for the case of the half-metallic ferromagnet Co2MnGe. The feasibility of HAXPES to explore the valence band electronic structure in deeply buried metallic layers is demonstrated for buried Co2MnSi films. The films exhibit the same valence density of states as bulk samples and confirm the promise of an epitaxial, single-crystalline Co2-based Heusler compound film as a ferromagnetic electrode for spintronics devices. The study of complete CoFe(B)/MgO/CoFe(B) tunneling junctions demonstrates the capability of HAXPES to explore the electronic structure in deeply buried layers in a non-destructive way. The improvement of the TMR by annealing of the junction is explained by an improvement of the structure together with a change of the composition in the CoFeB layers.

Keywords

Valence Band Partial Cross Section Magnetic Tunnel Junction Valence Band Spectrum Heusler Compound 
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.

Notes

Acknowledgements

This work was financially supported by the Deutsche Forschungsgemeinschaft (project P 7 in DfG research unit FOR 559). The authors are very grateful to K. Kobayashi, S. Ueda, Y. Yamashita, H. Yoshikawa (NIMS, SPring-8, Japan), E. Ikenaga, T. Sugiyama, N. Kawamura, and M. Suzuki (JASRI, SPring-8, Japan) for help with the synchrotron experiments. Thin film samples were provided by T. Ishikawa, T. Taira, T. Uemura, M. Yamamoto (Hokkaido University, Sapporo, Japan), S. Ikeda, H. Ohno (Tohoku University, Sendai, Japan), K. Inomata, H. Sukegawa, and W. Wang (National Institute for Materials Science, Tsukuba, Japan). The authors thank B. Balke, A. Gloskowski, X. Kozina, S. Ouardi, and G. Stryhanyuk (JoGU Mainz) for help with the experiments, for providing bulk samples as well as experimental XRD and magnetization data. Further financial support for the set-up of the phase retarder at BL47XU was provided by DfG-JST (FE633/6-1). The synchrotron radiation HAXPES measurements were performed at BL47XU with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposal Nos. 2008B0017, 2009B0017) and at BL15XU under the approval of the NIMS beamline station (Proposal Nos. 2007A4903, 2007B4907).

References

  1. 1.
    Siegbahn K (2005) Nucl Instrum Methods Phys Res A 547:2005 CrossRefGoogle Scholar
  2. 2.
    Lindau I, Pianetta P, Doniach S, Spicer WE (1974) Nature 250:214 CrossRefGoogle Scholar
  3. 3.
    Kobayashi K, Yabashi M, Takata Y, Tokushima T, Shin S, Tamasaku K, Miwa D, Ishikawa T, Nohira H, Hattori T, Sugita Y, Nakatsuka O, Sakai A, Zaima S (2003) Appl Phys Lett 83:1005 CrossRefGoogle Scholar
  4. 4.
    Various authors (2005) Nucl Instr Methods Phys Res A 547:1–238 Google Scholar
  5. 5.
    Kobayashi K (2009) Nucl Instr Methods Phys Res A 601:32 CrossRefGoogle Scholar
  6. 6.
    Ueda S, Tanaka H, Ikenaga E, Kim JJ, Ishikawa T, Kawai T, Kobayashi K (2009) Phys Rev B 80:092402 CrossRefGoogle Scholar
  7. 7.
    Fecher GH, Balke B, Gloskowskii A, Ouardi S, Felser C, Ishikawa T, Yamamoto M, Yamashita Y, Yoshikawa H, Ueda S, Kobayashi K (2008) Appl Phys Lett 92:193513 CrossRefGoogle Scholar
  8. 8.
    Sato H, Shimada K, Arita M, Takeda Y, Sawada M, Nakatake M, Yoshikawa K, Namatame H, Takata Y, Kobayashi K, Ikenaga E, Shin S, Yabashi M, Miwa D, Nishino Y, Tamasaku K, Ishikawa T, Hiraoka K, Kojima K, Taniguchi M (2004) Physica B 351:298 CrossRefGoogle Scholar
  9. 9.
    Kuznetsov VV, Cherepkov NA, Fecher GH, Schönhense G (1999) J Chem Phys 110:9997 CrossRefGoogle Scholar
  10. 10.
    Panaccione G, Cautero G, Cautero M, Fondacaro A, Grioni M, Lacovig P, Monaco G, Offi F, Paolicelli G, Sacchi M, Stojic N, Stefani G, Tommasini R, Torelli P (2005) J Phys Condens Matter 17:2671 CrossRefGoogle Scholar
  11. 11.
    Sekiyama A, Yamaguchi J, Higashia A, Obara M, Sugiyama H, Kimura MY, Suga S, Imada S, Nekrasov IA, Yabashi M, Tamasaku K, Ishikawa T (2010) New J Phys 12:043045 CrossRefGoogle Scholar
  12. 12.
    Kobayashi K (2005) Nucl Instrum Methods Phys Res A 547:98 CrossRefGoogle Scholar
  13. 13.
    Kim J, Ikenaga E, Kobata M, Takeuchi A, Awaji M, Makino H, Chen PP, Yamamoto A, Matsuoka T, Miwa D, Nishino Y, Yamamoto T, Yao T, Kobayashi K (2006) Surf Sci 252:5602 CrossRefGoogle Scholar
  14. 14.
    Reiss G, Schmalhorst J, Thomas A, Hütten A, Yuasa S (2007) Springer Tracts Mod Phys 227:291 CrossRefGoogle Scholar
  15. 15.
    Wüstenberg J, Fischer J, Herbort C, Jourdan M, Aeschlimann M, Cinchetti M (2007) J Phys D, Appl Phys 42:084016 CrossRefGoogle Scholar
  16. 16.
    Jang Y, Nam C, Lee KS, Choa BK, Cho YJ, Kim KS, Kim KW (2007) Appl Phys Lett 91:102104 CrossRefGoogle Scholar
  17. 17.
    Felser C, Elmers HJ, Fecher GH (2005) Lect Notes Phys 676:113 CrossRefGoogle Scholar
  18. 18.
    Wurmehl S, Fecher GH, Kroth K, Kronast F, Dürr HA, Takeda Y, Saitoh Y, Kobayashi K, Lin HJ, Schönhense G, Felser C (2006) J Phys D, Appl Phys 39:803 CrossRefGoogle Scholar
  19. 19.
    Balke B, Fecher GH, Kandpal HC, Felser C, Kobayashi K, Ikenaga E, Kim JJ, Ueda S (2006) Phys Rev B 74:104405 CrossRefGoogle Scholar
  20. 20.
    Fecher GH, Balke B, Ouardi S, Felser C, Schönhense G, Ikenaga E, Kim JJ, Ueda S, Kobayashi K (2007) J Phys D, Appl Phys 40:1576 CrossRefGoogle Scholar
  21. 21.
    Ouardi S, Balke B, Gloskovskii A, Fecher GH, Felser C, Schönhense G, Ishikawa T, Uemura T, Yamamoto M, Sukegawa H, Wang W, Inomata K, Yamashita Y, Yoshikawa H, Ueda S, Kobayashi K (2009) J Phys D, Appl Phys 42:084010 CrossRefGoogle Scholar
  22. 22.
    Ouardi S, Gloskovskii A, Balke B, Jenkins CA, Barth J, Fecher GH, Felser C, Gorgoi M, Mertin M, Schäfers F, Ikenaga E, Yang K, Kobayashi K, Kubota T, Oogane M, Ando Y (2009) J Phys D, Appl Phys 42:084011 CrossRefGoogle Scholar
  23. 23.
    Suzuki M, Kawamura N, Mizukami M, Urata A, Maruyama H, Goto S, Ishikawa T (1998) Jpn J Appl Phys 37:L1488 CrossRefGoogle Scholar
  24. 24.
    Tanuma S, Powell CJ, Penn DR (1993) Surf Interface Anal 21:165 CrossRefGoogle Scholar
  25. 25.
    Miyamoto K, Kimura A, Miura Y, Shirai M, Ye M, Cui Y, Shimada K, Namatame H, Taniguchi M, Takeda Y, Saitoh Y, Ikenaga E, Ueda S, Kobayashi K, Kanomata T (2009) Phys Rev B 79:1004205(R) Google Scholar
  26. 26.
    Fecher GH, Gloskovskii A, Kroth K, Barth J, Balke B, Felser C, Schäfers F, Mertin M, Eberhardt W, Mähl S, Schaff O (2007) J Electron Spectrosc Relat Phenom 156–158:97 CrossRefGoogle Scholar
  27. 27.
    Kijima H, Ishikawa T, Marukame T, Koyama H, Matsuda K, Uemura T, Yamamoto M (2006) IEEE Trans Magn 42:2688 CrossRefGoogle Scholar
  28. 28.
    Kijima H, Ishikawa T, Marukame T, Matsuda KI, Uemura T, Yamamoto M (2007) J Magn Magn Mater 310:2006 CrossRefGoogle Scholar
  29. 29.
    Marukame T, Kijima H, Ishikawa T, Matsuda KI, Uemura T, Yamamoto M (2007) J Magn Magn Mater 310:1946 CrossRefGoogle Scholar
  30. 30.
    Ishikawa T, Marukame T, Kijima H, Matsuda Ki, Uemura T, Yamamoto M (2006) Appl Phys Lett 89:192505 CrossRefGoogle Scholar
  31. 31.
    Ishikawa T, Hakamata S, Matsuda KI, Uemura T, Yamamoto M (2008) J Appl Phys 103:07A919 CrossRefGoogle Scholar
  32. 32.
    Kandpal HC, Fecher GH, Felser C, Schönhense G (2006) Phys Rev B 73:094422 CrossRefGoogle Scholar
  33. 33.
    Kandpal HC, Fecher GH, Felser C (2007) J Phys D, Appl Phys 40:1507 CrossRefGoogle Scholar
  34. 34.
    Lee YM, Hayakawa J, Ikeda S, Matsukura F, Ohno H (2007) Appl Phys Lett 90:212507 CrossRefGoogle Scholar
  35. 35.
    Lee YM, Hayakawa J, Ikeda S, Matsukura F, Ohno H (2006) Appl Phys Lett 89:042506 CrossRefGoogle Scholar
  36. 36.
    Ikeda S, Hayakawa J, Ashizawa Y, Lee YM, Miura K, Hasegawa H, Tsunoda M, Matsukura F, Ohno H (2008) Appl Phys Lett 93:082508 CrossRefGoogle Scholar
  37. 37.
    Masuda M, Uemura T, Matsuda Ki, Yamamoto M (2008) IEEE Trans Magn 44:3996 CrossRefGoogle Scholar
  38. 38.
    Wang WH, Sukegawa H, Shan R, Mitani S, Inomata K (2009) Appl Phys Lett 95:182502 CrossRefGoogle Scholar
  39. 39.
    Cherepkov NA, Kuznetsov VV, Verbitskii VA (1995) J Phys B, At Mol Opt Phys 28:1221 CrossRefGoogle Scholar
  40. 40.
    Hillebrecht FU, Roth C, Rose HB, Park WG, Kisker E, Cherepkov NA (1996) Phys Rev B 53:12182 CrossRefGoogle Scholar
  41. 41.
    Tobin JG, Goodman KW, Schumann FO, Willis RF, Kortright JB, Denlinger JD, Rotenberg E, Warwick A, Smith NV (1998) Surf Sci 395:L227 CrossRefGoogle Scholar
  42. 42.
    Henk J, Niklasson AMN, Johansson B (1999) Phys Rev B 59:13986 CrossRefGoogle Scholar
  43. 43.
    Bansmann J, Lu L, Meiwes-Broer KH, Schlathölter T, Braun J (1999) Phys Rev B 60:13860 CrossRefGoogle Scholar
  44. 44.
    Thole BT, van der Laan G (1991) Phys Rev B 44:12424 CrossRefGoogle Scholar
  45. 45.
    Thole BT, van der Laan G (1993) Phys Rev B 48:210 CrossRefGoogle Scholar
  46. 46.
    Thole BT, van der Laan G (1994) Phys Rev B 49:9613 CrossRefGoogle Scholar
  47. 47.
    van der Laan G, Thole BT (1994) Phys Rev B 52:15355 CrossRefGoogle Scholar
  48. 48.
    van der Laan G, Dhesi SS, Dudzik E (2000) Phys Rev B 61:12277 CrossRefGoogle Scholar
  49. 49.
    Fecher GH (1995) Europhys Lett 29:605 CrossRefGoogle Scholar
  50. 50.
    Venus D (1997) Phys Rev B 56:2661 CrossRefGoogle Scholar
  51. 51.
    Nakagawa T, Yokoyama T (2006) Phys Rev Lett 96:237402 CrossRefGoogle Scholar
  52. 52.
    Hild K, Maul J, Schönhense G, Elmers HJ, Amft M, Oppeneer PM (2009) Phys Rev Lett 102:057207 CrossRefGoogle Scholar
  53. 53.
    Rossi G, Panaccione G, Sirotti F, Lizzit S, Baraldi A, Paolucci G (1997) Phys Rev B 55:11488 CrossRefGoogle Scholar
  54. 54.
    Smith RJ, Anderson J, Lapeyre GJ (1976) Phys Rev Lett 37:1081 CrossRefGoogle Scholar
  55. 55.
    Cherepkov NA, Schönhense G (1993) Europhys Lett 24:79 CrossRefGoogle Scholar
  56. 56.
    Cherepkov NA, Raseev G (1995) J Chem Phys 103:8238 CrossRefGoogle Scholar
  57. 57.
    Kabachnik NM (1996) J Electron Spectrosc Relat Phenom 79:269 CrossRefGoogle Scholar
  58. 58.
    Ostertag C, Bansmann J, Grünewald C, Jentzsch T, Oelsner A, Fecher GH, Schönhense G (1995) Surf Sci 331–333:1197 CrossRefGoogle Scholar
  59. 59.
    Fecher GH, Oelsner A, Schicketanz M, Schönhense G (1998) J Electron Spectrosc Relat Phenom 88–91:185 CrossRefGoogle Scholar
  60. 60.
    Matsushita T, Imada S, Daimon H, Okuda T, Yamaguchi K, Miyagi H, Suga S (1997) Phys Rev B 56:7687 CrossRefGoogle Scholar
  61. 61.
    de Groot RA, Müller FM, van Engen PG, Buschow KHJ (1983) Phys Rev Lett 50:2024 CrossRefGoogle Scholar
  62. 62.
    Aliev FG (1991) Physica B 171:199 CrossRefGoogle Scholar
  63. 63.
    Miyamoto K, Kimura K, Sakamoto K, Ye M, Cui Y, Shimada K, Namatame H, Taniguchi M, Fujimori SI, Saitoh Y, Ikenaga E, Kobayashi K, Tadano J, Kanomata T (2008) Appl Phys Express 1:081901 CrossRefGoogle Scholar
  64. 64.
    Ouardi S, Fecher GH, Balke B, Kozina X, Stryganyuk G, Felser C, Lowitzer S, Ködderitzsch D, Ebert H, Ikenaga E (2010) Phys Rev B 085108 Google Scholar
  65. 65.
    Fadley CS (2005) Nucl Instrum Methods Phys Res A 647:24 CrossRefGoogle Scholar
  66. 66.
    Cooper J, Zare RN (1968) J Chem Phys 48:942 CrossRefGoogle Scholar
  67. 67.
    Cooper JW (1990) Phys Rev A 42:6942 CrossRefGoogle Scholar
  68. 68.
    Kuznetsov VV, Cherepkov NA, Fecher GH, Schönhense G (2002) J Chem Phys 117:7180 CrossRefGoogle Scholar
  69. 69.
    Fecher GH, Kuznetsov VV, Cherepkov NA, Schönhense G (2002) J Electron Spectrosc Relat Phenom 122:157 CrossRefGoogle Scholar
  70. 70.
    Chandra N (1987) J Phys B, At Mol Phys 20:3417 CrossRefGoogle Scholar
  71. 71.
    Daimon H, Imada S, Suga S (2001) Surf Sci 471:143 CrossRefGoogle Scholar
  72. 72.
    Oelsner A, Schicketanz M, Fecher GH, Schönhense G, Morais J (2002) Surf Rev Lett 9:889 CrossRefGoogle Scholar
  73. 73.
    Rennert P (2001) J Electron Spectrosc Relat Phenom 119:1 CrossRefGoogle Scholar
  74. 74.
    Hemmers O, Guillemin R, Lindle DW (2004) Radiat Phys Chem 70:123 CrossRefGoogle Scholar
  75. 75.
    Fadley CS (2010) J Electron Spectrosc Relat Phenom 178–179:2 CrossRefGoogle Scholar
  76. 76.
    Zegenhagen J, Detlefs B, Lee TL, Thiess S, Isern H, Petit L, Andre L, Roy J, Mi Y, Joumard I (2010) J Electron Spectrosc Relat Phenom 178–179:258 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Institut für Anorganische Chemie und Analytische ChemieJohannes Gutenberg – UniversitätMainzGermany
  2. 2.Max-Planck-Institut für Chemische Physik fester StoffeDresdenGermany

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