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Magnetocapacitance and exponential magnetoresistance in manganite-titanate heterojunctions

N. Nakagawa·M. Asai·Y. Mukunoki·T. Susaki·H. Y. Hwang
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Abstract

We present a rectifying manganite-titanate heterojunction exhibiting a magnetic field tunable depletion layer. This creates a large positive magnetocapacitance, a direct measure of the field-induced reduction of the effective depletion width across the junction. Furthermore, the reduction of the junction barrier shifts the forward bias characteristics, giving exponentially-enhanced differential magnetoresistance, occurring despite the absence of a spin filter. These results provide a unique probe of a Mott insulator/band insulator interface, and further suggest new electronic devices incorporating the magnetic field sensitivity of these strongly correlated electron materials.

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N. Nakagawa, M. Asai, Y. Mukunoki, T. Susaki, H. Y. Hwang. 2004-09-21. Magnetocapacitance and exponential magnetoresistance in manganite-titanate heterojunctions. https://doi.org/10.1063/1.1868882

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