Interface Magnetoresistance in Manganite-Titanate Heterojunctions

T. Susaki; N. Nakagawa; H. Y. Hwang

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Interface Magnetoresistance in Manganite-Titanate Heterojunctions

T. Susaki·N. Nakagawa·H. Y. Hwang

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Abstract

We have found that the current- voltage characteristics of La0.7Sr0.3MnO3(-delta)/Nb:SrTiO3 rectifying junctions are quantitatively well-described by (thermally-assisted) tunneling with an effectively temperature-independent Schottky barrier under no magnetic field, while those of the oxygen deficient junction remarkably deviate from such a simple behavior as magnetic field is applied. These results indicate a new form of magnetoresistance arising from magnetic field changes of the interface band diagram via the strong electron-spin coupling in manganites.

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T. Susaki, N. Nakagawa, H. Y. Hwang. 2006-09-13. Interface Magnetoresistance in Manganite-Titanate Heterojunctions. https://arxiv.org/abs/cond-mat/0609315

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