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Four-probe Magnetoresistance of Current-perpendicular-to-plane Structures

Published online by Cambridge University Press:  26 February 2011

Hua Zhou
Affiliation:
[email protected], Seagate Technology, 1251 Waterfront Place, Pittsburgh, PA, 15222, United States
Mark W. Covington
Affiliation:
[email protected], Seagate Technology, United States
Michael A. Seigler
Affiliation:
[email protected], Seagate Technology, United States
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Abstract

The resistance and magnetoresistance (MR) of three-dimensional current-perpendicular-to-plane (CPP) structures have been calculated via numerical finite element solutions of the Laplace equation. This model accounts for the non-uniform current paths in a four-probe geometry that can yield MR that differs from the intrinsic MR of the isolated CPP pillar with spatially uniform current flow. We calculated the four-probe MR for various geometries and resistivities of both the normal metal leads and the magnetoresistive pillar. From a single, unified approach, we are able to consistently account for the disparate behavior that has been previously published. In particular, we identify conditions that produce four-probe MR that differs from the intrinsic MR of the CPP pillar and highlight those situations where the four-probe resistance is negative. Finally, we present a simple analytical formula for the MR ratio that is applicable to narrow CPP pillars with wide, thin leads.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

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References

[1] Pratt, J., P., W., Lee, S.-F., Slaughter, J. M., Loloee, R., Schroeder, P. A., and Bass, J., Phys. Rev. Lett. 66, 3060 (1991).Google Scholar
[2] Spallas, J. P., Mao, M., Law, B., Grabner, F., O'Kane, D., and Cerjan, C., IEEE Trans. Magn. 33, 3391 (1997).Google Scholar
[3] Seigler, M. A., van der Heijden, P. A. A., Litvinov, A. E., and Rottmayer, R. E., IEEE Trans. Magn. 39, 1855 (2003).Google Scholar
[4] Lenczowski, S. K. J., van de Veerdonk, R. J. M., Gijs, M. A. M., Giesbers, J. B., and Janssen, H. H. J. M., J. Appl. Phys. 75, 5154 (1994).Google Scholar
[5] Moodera, J. S., Kinder, L. R., Nowak, J., LeClair, P., and Meservey, R., Appl. Phys. Lett. 69, 708 (1996).Google Scholar
[6] Pedersen, R. J. and Vernon, F. L. Jr., Appl. Phys. Lett. 10, 29 (1967).Google Scholar
[7] van de Veerdonk, R. J. M., Nowak, J., Meservey, R., Moodera, J. S., and de Jonge, W. J. M., Appl. Phys. Lett. 71, 2839 (1997).Google Scholar
[8] Matsuda, K., Watari, N., Kamijo, A., and Tsuge, H., Appl. Phys. Lett. 77, 3060 (2000).Google Scholar
[9] Chen, J., Li, Y., Nowak, J., and de-Castro, J. Fernandez, J. Appl. Phys. 91, 8783 (2002).Google Scholar
[10] Bussmann, K., Cheng, S. F., Prinz, G. A., Hu, Y., Gutmann, R., Wang, D., and Beech, R., IEEE Trans. Magn. 34, 924 (1998).Google Scholar
[11] Spallas, J. P., Huai, Y., Vernon, S., Fuchs, B., Law, B., R, D.. Kania, Kroes, D., Thomas, M., O'Kane, D., and Tan, Z. C. H., IEEE Trans. Magn. 32, 4710 (1996).Google Scholar
[12] Seyama, Y., Tanaka, A., and Oshiki, M., IEEE Trans. Magn. 35, 2838 (1999).Google Scholar