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arXiv · 1310.1466

Effect of "dipolar-biasing" on the tunability of tunneling magnetoresistance in transition metal oxide systems

P. Anil Kumar·D. D. Sarma
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Abstract

We observe an unusual tunneling magnetoresistance (TMR) phenomenon in a composite of La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ with CoFe$_{2}$O$_{4}$ where the TMR versus applied magnetic field loop suggests a "negative coercive field". Tracing its origin back to a "dipolar-biasing" of La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ by CoFe$_{2}$O$_{4}$, we show that the TMR of even a single composite can be tuned continuously so that the resistance peak or the highest sensitivity of the TMR can be positioned anywhere on the magnetic field axis with a suitable magnetic history of the sample. This phenomenon of an unprecedented tunability of the TMR should be present in general in all such composites.

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P. Anil Kumar, D. D. Sarma. 2013-10-05. Effect of "dipolar-biasing" on the tunability of tunneling magnetoresistance in transition metal oxide systems. https://doi.org/10.1063/1.4731206

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