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Anomalous enhancement in interfacial perpendicular magnetic anisotropy through uphill diffusion.

ABSTRACT: We observed interfacial chemical sharpening due to uphill diffusion in post annealed ultrathin multilayer stack of Co and Pt, which leads to enhanced interfacial perpendicular magnetic anisotropy (PMA). This is surprising as these elements are considered as perfectly miscible. This chemical sharpening was confirmed through quantitative energy dispersive x-ray (EDX) spectroscopy and intensity distribution of images taken on high angle annular dark field (HAADF) detector in Scanning Transmission Electron Microscopic (STEM) mode. This observation demonstrates an evidence of miscibility gap in ultrathin coherent Co/Pt multilayer stacks.

SUBMITTER: Das T

PROVIDER: S-EPMC4060506 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Anomalous enhancement in interfacial perpendicular magnetic anisotropy through uphill diffusion.

Das Tanmay T Kulkarni Prabhanjan D PD Purandare S C SC Barshilia Harish C HC Bhattacharyya Somnath S Chowdhury Prasanta P

Scientific reports 20140617

We observed interfacial chemical sharpening due to uphill diffusion in post annealed ultrathin multilayer stack of Co and Pt, which leads to enhanced interfacial perpendicular magnetic anisotropy (PMA). This is surprising as these elements are considered as perfectly miscible. This chemical sharpening was confirmed through quantitative energy dispersive x-ray (EDX) spectroscopy and intensity distribution of images taken on high angle annular dark field (HAADF) detector in Scanning Transmission E ...[more]

PMID: 24937637

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