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Anomalous bias dependence of tunnel magnetoresistance in a magnetic tunnel junction

Soumik Mukhopadhyay·I. Das·S. P. Pai·P. Raychaudhuri
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Abstract

We have fabricated a spin-polarized tunneling device based on half metallic manganites incorporating $Ba_{2}LaNbO_{6}$ as insulating barrier. An anomalous bias dependence of tunnel magnetoresistance (TMR) has been observed, the first of its kind in a symmetric electrode tunnel junction with single insulating barrier. The bias dependence of TMR shows an extremely sharp zero bias anomaly, which can be considered as a demonstration of the drastic density of states variation around the Fermi level of the half metal. This serves as a strong evidence for the existence of minority spin tunneling states at the half-metal insulator interface.

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Soumik Mukhopadhyay, I. Das, S. P. Pai, P. Raychaudhuri. 2005-04-07. Anomalous bias dependence of tunnel magnetoresistance in a magnetic tunnel junction. https://doi.org/10.1063/1.1901823

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