| Autor: |
Gareev, R. R., Pohlmann, L. L., Stein, S., Bürgler, D. E., Grünberg, P. A., Siegel, M. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 5/15/2003, Vol. 93 Issue 10, p8038, 3p, 1 Black and White Photograph, 1 Chart, 4 Graphs |
| Abstrakt: |
Fe(5 nm)/Si(0.8-2 nm)/Fe(5 nm) structures are grown by molecular-beam epitaxy on Ag(001) buffered GaAs substrates. Ferromagnetic tunneling junctions with crossed electrodes and junction areas ranging from 22 to 225 μm[SUP2]are patterned using photolithography. Antiparallel alignment of the magnetizations due to antiferromagnetic interlayer coupling, which is confirmed by longitudinal magneto-optical Kerr effect hysteresis loops, exists for the whole range of spacer thicknesses. Transport properties in current perpendicular to the sample plane geometry are examined by the four-point method in the temperature range from 4 K to room temperature. As a function of spacer thickness, the junctions show a strong increase of the resistance times area product from ∼1Ω μm[SUP2]to more than 10 kΩ μm[SUP2]. The dI/dV-V curves are parabolic and asymmetric and thus characteristic for trapezoidal tunneling barriers. The mean barrier heights derived from Brinkman fits range from 0.3 to 0.8 eV. The zero-bias resistance of the tunneling junctions moderately decreases with temperature by less than 10% over the whole measured temperature range. All these transport properties fulfill the necessary and sufficient criteria for elastic tunneling. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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