Hostname: page-component-745bb68f8f-b6zl4 Total loading time: 0 Render date: 2025-02-11T12:06:12.619Z Has data issue: false hasContentIssue false
  • English
  • Français

Half-Metallic Ferromagnetic Oxides

Published online by Cambridge University Press:  31 January 2011

J.M.D. Coey  and
C.L. Chien
Get access

Abstract

Half-metals are unusual ferromagnets that have electrons at the Fermi level in a single spin state, either spin up or spin down. Of potential interest as sources and analyzers of polarized electrons in spintronic devices, they are usually identified from spin-dependent band-structure calculations. We present a classification scheme for half-metals and then discuss methods for measuring spin polarization based on point contacts or tunnel junctions with ferromagnetic or superconducting counter electrodes. Oxide examples include CrO2, the best-studied half-metal. The half-metallicity tends to be destroyed by increasing temperature and by structural defects. The half-metals that currently offer the best prospects for spintronics applications are those with the highest Curie temperatures, such as magnetite, Fe3O4, and perhaps oxide semiconductors such as Co-doped ZnO.

Keywords

Andreev reflectionCrO2Fe3O4ferromagnetic oxideshalf-metalsspin-polarized materialsspintronicstunneling
Type
Research Article
Information
MRS Bulletin , Volume 28 , Issue 10: New Materials for Spintronics , October 2003 , pp. 720 - 724
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. For a general reference on spintronics (principles, materials, and devices), see Ziese, M. and Thornton, M.F., eds., Spin Electronics (Springer, Berlin, 2001).CrossRefGoogle Scholar
2.Prinz, G.A., Science 282 (1998) p. 1660.CrossRefGoogle Scholar
3.Monsma, D.J. and Parkin, S.S.P., Appl. Phys Lett. 77 (2000) p. 720.CrossRefGoogle Scholar
4.Coey, J.M.D., Venkatesan, M., and Bari, M.A., in High Magnetic Fields, edited by Berthier, C., Lévy, L.P., and Martinez, G. (Springer, Berlin, 2002) p. 377.CrossRefGoogle Scholar
5.Coey, J.M.D. and Venkatesan, M., J. Appl. Phys. 91 (2002) p. 8345.CrossRefGoogle Scholar
6.de Groot, R.A., Mueller, F.M., van Engen, P.G., and Buschow, K.H.J., Phys. Rev. Lett. 50 (1983) p. 2024.CrossRefGoogle Scholar
7.Mazin, I.I., Phys. Rev. Lett. 83 (1999) p. 1427.CrossRefGoogle Scholar
8.de Teresa, J.M., Barthélémy, A., Fert, A., Contuor, J.P., Montaigne, F., and Seneor, P., Science 286 (1999) p. 507.CrossRefGoogle Scholar
9.Coey, J.M.D., Versluijs, J.J., and Venkatesan, M., J. Phys. D: Appl. Phys. 35 (2002) p. 2457.CrossRefGoogle Scholar
10.Meservey, R. and Tedrow, P.M., Phys. Rep. 238 (1994) p. 173.CrossRefGoogle Scholar
11.Soulen, R.J. Jr., Byers, J.M., Osofsky, M.S., Nadgorny, B., Ambrose, T., Cheng, S.F., Broussard, P.R., Tanaka, C.T., Nowak, J., Moodera, J.S., Barry, A., and Coey, J.M.D., Science 282 (1998) p. 88.CrossRefGoogle Scholar
12.Parker, J.S., Watts, S.M., Ivanov, P.G., and Xiong, P., Phys. Rev. Lett. 88 196601 (2002).CrossRefGoogle Scholar
13.Ji, Y., Strijkers, G.L., Yang, F.Y., Chien, C.L., Byers, J.M., Anguelouch, A., Xiao, G., and Gupta, A., Phys. Rev. Lett. 86 (2001) p. 5585.CrossRefGoogle Scholar
14.Kobayashi, K.I., Kimura, T., Sawada, H., Tekura, K.K., and Tokura, Y., Nature 395 (1998) p. 677.CrossRefGoogle Scholar
15.Barthélémy, A. et al. (unpublished).Google Scholar
16.Coey, J.M.D., Viret, M., and von Molnar, S., Adv. Phys. 48 (1999) p. 167.CrossRefGoogle Scholar
17.Bowen, M., Bibes, M., Barthélémy, A., Contour, J.-P., Anane, A., Lemaitre, Y., and Fert, A., Appl. Phys. Lett. 82 (2003) p. 233.CrossRefGoogle Scholar
18.Worledge, D.C. and Geballe, T.H., Appl. Phys. Lett. 76 (2000) p. 900.CrossRefGoogle Scholar
19.Ji, Y., Chien, C.L., Tomioka, Y., and Tokura, Y., Phys. Rev. B 66 012410 (2002).CrossRefGoogle Scholar
20.Nadgorny, B., Mazin, I.I., Osofsky, M., Soulen, R.J. Jr., Broussard, P., Stroud, R.M., Singh, D.J., Harris, V.G., Arsenov, A., and Mukovskii, Ya., Phys. Rev. B 63 184433 (2001).CrossRefGoogle Scholar
21.Penicaud, M., Silberchiot, B., Sommers, C.B., and Kubler, J., J. Magn. Magn. Mater. 103 (1992) p. 212.CrossRefGoogle Scholar
22.Brabers, V.A.M., in Ferromagnetic Materials, Vol. 8, edited by Buschow, K.H.J. (Elsevier, Amsterdam, 1995) p. 189.Google Scholar
23.Dedkov, Yu. S., Rüdiger, U., and Güntherodt, G., Phys. Rev. B 65 064417 (2002).CrossRefGoogle Scholar
24.Hu, G. and Suzuki, Y., Phys. Rev. Lett. 89 276601 (2002).CrossRefGoogle Scholar
25.Singh, D.J., Phys Rev. B 55 (1997) p. 313.CrossRefGoogle Scholar
26.Edmonds, K.W., Wang, K.Y., Campion, R.P., Neumann, A.C., Gallagher, B.L., Foxon, C.T., and Main, P.C., Appl. Phys. Lett. 81 (2002) p. 4991.CrossRefGoogle Scholar
27.Braden, J.G., Parker, J.S., Xiong, P., Chun, S., and Samarth, N.Phys. Rev. Lett. 91 056602 (2003).CrossRefGoogle Scholar
28.Ueda, K., Tabata, H., and Kawai, T., Appl. Phys. Lett. 79 (2001) p. 988.CrossRefGoogle Scholar
29.Ogale, S.B., Choudhary, R.J., Buban, J.P., Lofland, S.E., Shinde, S.R., Kale, S.N., Kulkarni, V.N., Higgins, J., Lanci, C., Simpson, J.R., Browning, N.D., Das Sarma, S., Drew, H.D., Greene, R.L., and Venkatesan, T., Los Alamos National Laboratory Preprint Server cond-mat/0301456 (2003).Google Scholar
30.Matsumoto, Y., Murakami, M., Shono, T., Hasegawa, T., Fukumura, T., Kawasaki, M., Ahmet, P., Chikyow, T., Koshihara, S.-Y., and Koinuma, H., Science 291 (2001) p. 854.CrossRefGoogle Scholar