Low Voltage I-V Characteristics in Magnetic Tunnel Junctions

G. G. Cabrera; N. Garcia

doi:10.1063/1.1433168

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arXiv · cond-mat/0106123

Low Voltage I-V Characteristics in Magnetic Tunnel Junctions

G. G. Cabrera·N. Garcia

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Abstract

We show that elastic currents that take into account variations of the tunnel transmitivity with voltage and a large ratio of majority to minority spin densities of states of the $s$ band, can account for the low voltage current anomalies observed in magnet-oxide-magnet junctions. The anomalies can be positive, negative or have a mixed form, depending of the position of the Fermi level in the $s$ band, in agreement with observations. Magnon contribution is negligible small to account for the sharp drop of the magnetoresistance with the voltage bias.

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G. G. Cabrera, N. Garcia. 2001-06-06. Low Voltage I-V Characteristics in Magnetic Tunnel Junctions. https://doi.org/10.1063/1.1433168

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