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arXiv · 1306.3453

Interfacial Magnetism in Manganite Superlattices

Kalpataru Pradhan·Arno P. Kampf
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Abstract

We use a two-orbital double-exchange model including Jahn-Teller lattice distortions, superexchange interactions, and long-range Coulomb (LRC) interactions to investigate the origin of magnetically disordered interfaces between ferromagnetic metallic (FM) and antiferromagnetic insulating (AFI) manganites in FM/AFI superlattices. The induced magnetic moment in the AFI layer varies non-monotonically with increasing AFI layer width as seen in the experiment. We provide a framework for understanding this non-monotonic behavior which has a one-to-one correspondence with the magnetization of the FM interface. The obtained insights provide a basis for improving the tunneling magnetoresistance in FM/AFI manganite superlattices by avoiding a magnetic dead layer (MDL) in the FM manganite.

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Kalpataru Pradhan, Arno P. Kampf. 2013-06-14. Interfacial Magnetism in Manganite Superlattices. https://doi.org/10.1103/physrevb.88.115136

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