Abstract
Potential applications of systems based on half-metallic ferromagnets (HMFs) in magneto- and spinelectronics including spin injectors, magnetic field sensors and magnetic memory devices stimulated the investigation of the electronic properties of HFMs by a multitude of experimental and theoretical approaches. The main question remains however if the 100% spin polarization at the Fermi level (E F) theoretically predicted for HFMs can be confirmed experimentally. This article gives a short overview on the half-metallic ferromagnets with special emphasis on magnetite (Fe3O4) and chromium dioxide (CrO2). The spin-resolved electronic structure of thin epitaxial Fe3O4(111) and CrO2(100) films has been investigated at 293 K by means of spin-resolved photoemission spectroscopy (SP-PES). Epitaxial Fe3O4(111) films have been grown on different substrates by oxidizing epitaxial Fe(110) films. High surface quality and chemical homogeneity as well as high crystalline order in the bulk of Fe3O4(111) films were confirmed by means of STM and LEED. The Fe3O4(111) epitaxial films show a maximum spin polarization value of -(80±5)% near EF at 293 K confirming the half-metallic nature of Fe3O4 in the [111] direction. High-quality epitaxial CrO2(100) films have been prepared by a chemical vapor deposition technique. Near EF an energy gap was observed for spin-down electrons and a spin polarization of about +(90 ± 10)% was found at 293 K by means of SP-PES. This value and the magnitude of the gap in the minority spin channel are in good agreement with the prediction of the half-metallic nature of CrO2.
Preview
Unable to display preview. Download preview PDF.
References
K.-H. Schwarz: J. Phys. F: Met. Phys. 16, L211 (1986)
S.P. Lewis, P.B. Allen, T. Sasaki: Phys. Rev. B 55, 10253 (1997)
M.A. Korotin, V.I. Anisimov, D.I. Khomskii, G.A. Sawatzky: Phys. Rev. Lett. 80, 4305 (1998)
A. Yanase, K. Siratori: J. Phys. Soc. Jap. 53, 312 (1984)
Z. Zhang, S. Satpathy: Phys. Rev. B 44, 13319 (1991)
W.J. Gallagher et al: J. Appl. Phys. 81, 3741 (1997)
J.M. Daughton: J. Appl. Phys. 81, 3758 (1997)
H. Boeve, R.J.M. van der Veerdonk, B. Dutta, J. de Boeck, J.S. Moodera, G. Borghs: J. Appl. Phys. 83, 6700 (1998)
M. Jullière: Phys. Lett. A 54, 225 (1975)
R.A. de Groot, F. Müller, P. van Engen, K.H.J. Buschow: Phys. Rev. Lett. 50, 2024 (1983)
J.-H. Park, E. Vescovo, H.-J. Kim, C. Kwon, R. Ramesh, T. Venkatesan: Nature 392, 794 (1998)
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, J.M.D. Coey: Science 282, 85 (1998)
T. Tsujioka, T. Mizokawa, J. Okamoto, A. Fujimori, M. Nohara, H. Takagi, K. Yamaura, M. Takano: Phys. Rev. B 56, R15509 (1997)
W.J. DeSisto, P.R. Broussard, T.F. Ambrose, B.E. Nadgorny, M.S. Osofsky: Appl. Phys. Lett. 76, 3789 (2000)
Y. Ji, G.J. Strijkers, F.Y. Yang, C.L. Chien, J.M. Byers, A. Anguelouch, G. Xiao, A. Gupta: Phys. Rev. Lett. 86, 5585 (2001)
A. Anguelouch, A. Gupta, Gang Xiao, D.W. Abraham, Y. Ji, S. Ingvarsson, C.L. Chien: Phys. Rev. B 64, R180408 (2001)
K.P. Kämper, W. Schmitt, G. Güntherodt, R.J. Gambino, and R. Ruf: Phys. Rev. Lett. 59, 2788 (1987)
V.Yu. Irkhin, M.I. Katsnel'son: Physics - Uspekhi 37, 659 (1994)
J.M.D. Coey, M. Venkatesan, M.A. Bari: Half-Metallic Ferromagnets. In: Lecture Notes in Physics, vol 595, ed by C. Bertheir, L. P. Lévy, and G. Martinez (Springer, Berlin Heidelberg New York 2002) pp 307-396
J.M.D. Coey, M. Venkatesan: J. Appl. Phys. 91, 8345 (2002)
R.A. de Groot, K.H.J. Buschow: J. Magn. Magn. Mater. 54-57, 1377 (1986)
J. Kübler: Physica B+C 127, 257 (1984)
R.A. de Groot, A.M. van der Kraan, K.H.J. Buschow: J. Magn. Magn. Mater. 61, 330 (1986)
K.I. Kobayashi, T. Kimura, H. Sawada, K. Terakura, Y. Tokura: Nature 395, 677 (1998)
W.E. Pickett, D.J. Singh: Phys. Rev. B 53, 1146 (1996)
P.K. deBoer, H. van Lenken, R.A. de Groot, T. Rojo, G.E. Barberis: Solid State Commun. 102, 621 (1997)
B. Nadgorny, I.I. Mazin, M. Osofsky, R.J. Soulen, P. Broussard, R.M. Stroud, D.J. Singh, V.G. Harris, A. Arsenov, Ya. Mukovskii: Phys. Rev. B 63, 184433 (2001)
D.J. Singh: Phys. Rev. B 55, 313 (1997)
N. Tsuda, K. Nasu, A. Yanase, K. Siratori: Electronic Conduction in Oxides, 1st edn (Springer, Berlin Heidelberg New York 1991) p 207
L. Néel: Ann. Phys. (Leipzig) 3, 137 (1948)
C.G. Shull, F.O. Wollan, W.C. Koehler: Phys. Rev. 84, 912 (1951)
E.J.W. Verwey, P.W. Haaymann: Physica (Amsterdam) 8, 979 (1941)
E.J.W. Verwey, P.W. Haayman, F.C. Romeijan: J. Chem. Phys. 15, 181 (1947)
J. Yoshida, S. Iida: J. Phys. Soc. Jpn. 42, 230 (1977)
S. Iida: Philos. Mag. B 42, 349 (1980)
N.F. Mott: Philos. Mag. B 42, 327 (1980)
V.A. Brabers: In: Ferromagnetic Materials, vol.8, ed. by K.H.J. Buschow, (Elsevier, Amsterdam, 1995) p 189
V.I. Anisimov, I.S. Elfimov, N. Hamada, K. Terakura: Phys. Rev. B 54, 4387 (1996)
H.-T. Jeng, G.Y. Guo: Phys. Rev. B 65, 094429 (2002)
V.N. Antonov, B.N. Harmon, V.P. Antropov, A. Ya. Perlov, A.N. Yaresko: Phys. Rev. B 64, 134410 (2001)
V.N. Antonov, B.N. Harmon, A.N. Yaresko: Phys. Rev. B 67, 024417 (2003)
S.F. Alvarado, W. Eib, F. Meier, D.T. Pierce, K. Sattler, H.C. Siegmann, J.P. Remeika: Phys. Rev. Lett. 34, 319 (1975)
S.F. Alvarado, M. Erbudak, P. Munz: Phys. Rev. B 14, 2740 (1976)
S.F. Alvarado, P.S. Bagus: Phys. Lett. A 67, 397 (1978)
H.-J. Kim, J.-H. Park, E. Vescovo: Phys. Rev. B 61, 15288 (2000)
S.A. Morton, G.D. Waddill, S. Kim, Ivan K. Schuller, S.A. Chambers, J.G. Tobin: Surf. Sci. 513, L451 (2002)
D.J. Huang, C.F. Chang, J. Chen, L.H. Tjeng, A.D. Rata, W.P. Wu, S.C. Chung, H.J. Lin, T. Hibma, C.T. Chen: J. Magn. Magn. Mater., 239, 261 (2002)
Yu.S. Dedkov, U. Rüdiger, G. Güntherodt: Phys. Rev. B 65, 064417 (2002)
J.J. Versluijs, M.A. Bari, J.M.D. Coey: Phys. Rev. Lett. 87, 026601 (2001)
V.S. Smentkowsky, J.T. Yates: Surf. Sci. 232, 113 (1990)
A. Wight, N.G. Condon, F.M. Leibsle, G. Worthy, A. Hodgson: Surf. Sci. 331-333, 133 (1995)
W. Weiss, A. Barbieri, M.A. Van Hove, G.A. Somorjai: Phys. Rev. Lett. 71, 1848 (1993)
A. Barbieri, W. Weiss, M.A. van Hove, G.A. Samorjai: Surf. Sci. 302, 259 (1994)
G.M. Gaines, P.J.H. Bloemen, J.T. Kohlhepp, C.W.T. Bulle-Lieuwma, R.M. Wolf, A. Reinders, R.M. Jungblut, P.A.A. van der Heijden, J.T.W.M. van Eemeren, J. van de Stegge, W. J.M. de Jonge: Surf. Sci. 373, 85 (1997)
Y.J. Kim, Y. Gao, S.A. Chambers: Surf. Sci. 371, 358 (1997)
W.F.J. Fontijn, R.M. Wolf, R. Metselaar, P.J. van der Zaag: Thin Solid Films 292, 270 (1997)
S.B. Ogale, K. Ghosh, R.P. Sharma, R.L. Greene, R. Ramesh, T. Venkatesan: Phys. Rev. B 57, 7823 (1998)
M. Ritter, W. Weiss: Surf. Sci. 432, 81 (1999)
F.C. Voogt, T. Fujii, P.J.M. Smulders, L. Niesen, M. A. James, T. Hibma: Phys. Rev. B 60, 11 193 (1999)
T. Fujii, F.M.F. de Groot, G.A. Sawatzki, F.C. Voogt, T. Hibma, K. Okada: Phys. Rev. B 59, 3195 (1999)
S.A. Chambers, S. Thevuthasan, S.A. Joyce: Surf. Sci. Lett. 450, L273 (2000)
M. Fonin, Yu. S. Dedkov, J. Mayer, U. Rüdiger, G. Güntherodt: Phys. Rev. B 68, 045414 (2003)
H.-J. Kim, J.-H. Park, E. Vescovo: Phys. Rev. B 61, 15284 (2000)
F.M.F. de Groot, M. Grioni, J.C. Fuggle, J. Ghijsen, G.A. Sawatzky, H. Petersen: Phys. Rev. B 40, 5715 (1989)
F.M.F. de Groot, J.C. Fuggle, B.T. Thole, G.A. Sawatzky: Phys. Rev. B 42, 5459 (1990)
R. Kurzawa, K.-P.- Kämper, W. Schmitt, G. Güntherodt: Solid State Commun. 60, 777, (1986)
H.- J. Kim, E. Vescovo: Phys. Rev. B 58, 14047 (1998)
G.Q. Gong, A. Gupta, G. Xiao, W. Qian, V.P. Dravid: Phys. Rev. B 56, 5096 (1997)
S.F. Alvarado: Z. Phys. B 33, 51 (1979)
D. Mauri, D. Scholl, H.C. Siegmann, E. Kay: Phys. Rev. Lett. 61, 758 (1988)
I.I. Mazin, D.J. Singh, C. Ambrosch-Draxl: Phys. Rev. B 59, 411 (1999)
R. Wiesendanger, H.-J. Güntherodt, G. Güntherodt, R.J. Gambino, R. Ruf: Phys. Rev. Lett. 65, 247 (1990)
Yu. S. Dedkov, M. Fonin, C. König, U. Rüdiger, G. Güntherodt: Appl. Phys. Lett. 80, 4181 (2002)
N. Heiman, N.S. Kazama: J. Appl. Phys. 50, 7333 (1979)
Author information
Authors and Affiliations
Editor information
Rights and permissions
About this chapter
Cite this chapter
Fonin, M., S. Dedkov, Y., Rüdiger, U., Güntherodt, G. Growth and Room Temperature Spin Polarization of Half-metallic Epitaxial CrO2 and Fe3O4 Thin Films. In: Donath, M., Nolting, W. (eds) Local-Moment Ferromagnets. Lecture Notes in Physics, vol 678. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11417255_18
Download citation
DOI: https://doi.org/10.1007/11417255_18
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-27286-1
Online ISBN: 978-3-540-31516-2
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)