论文信息 - Engineering the magnetic properties of Ge1-xMnx nanowires

Engineering the magnetic properties of Ge1-xMnx nanowires

Possible origins of room-temperature ferromagnetism in GeMn nanowires (NWs) are investigated. Arrays of Ge1−xMnx NWs and Ge∕Ge1−xMnx nanocables (NCs) (x=1%–5%) have been synthesized within the pores of anodized alumina oxide (AAO) membranes. The influence of annealing on the magnetic properties of Ge1−xMnx NWs is studied. The room-temperature ferromagnetism is preserved after the postfabrication annealing in inert atmosphere (Tann=750°C) demonstrating overall compatibility of Ge1−xMnx NWs with conventional complementary metal-oxide semiconductor technology. The role of oxygen in high-TC ferromagnetic ordering is investigated in double-phased NCs with a Ge sheath. Despite a barrier to oxygen migration from the AAO membrane, samples still display room-temperature ferromagnetism, hence, ruling out any significant role of oxygen in the explanation of the high TC in the system. The magnetic properties of the one-dimensional Ge1−xMnx nanostructures can be understood by considering interface related phenomena.

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