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arXiv · 0912.2615

STS study of the CMR effect of a manganite thin film in an external magnetic field

B. Damaschke·T. Mildner·V. Moshnyaga·K. Samwer
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Abstract

A La0.75Ca0.25MnO3-film grown by metalorganic aerosol deposition technique was investigated by scanning tunnelling microscopy and spectroscopy. A small spot was found on the surface which exhibits the expected magnetic field dependence of the tunnelling conductivity giving the opportunity for a local spectroscopic study of the intrinsic colossal magnetoresistance (CMR) behavior. The tunnelling conductivity is strongly enhanced in an external magnetic field of 4 T and the CMR behavior can be interpreted in terms of a redistribution of occupied electronic states torwards the Fermi energy.

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B. Damaschke, T. Mildner, V. Moshnyaga, K. Samwer. 2009-12-14. STS study of the CMR effect of a manganite thin film in an external magnetic field. https://arxiv.org/abs/0912.2615

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