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arXiv · 1211.0551

Polarized neutron reflectometry study of Fe16N2 with Giant Saturation Magnetization prepared by N Inter-diffusion in Annealed Fe-N Thin Films

Nian Ji·Valeria Lauter·Hailemariam Ambaye·Xiaowei Zhang·Sarbeswar Sahoo·Mike Kautzky·Mark Kief·Jian-Ping Wang
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Abstract

We report a synthesis route to grow iron nitride thin films with giant saturation magnetization (Ms) through an N inter-diffusion process. By post annealing Fe/Fe-N structured films grown on GaAs(001) substrates, nitrogen diffuses from the over-doped amorphous-like Fe-N layer into strained crystalline Fe layer and facilitates the development of metastable Fe16N2 phase. As explored by polarized neutron reflectometry, the depth-dependent Ms profile can be well described by a model with the presence of a giant Ms up to 2360 emu/cm3 at near-substrate interface, corresponding to the strained regions of these annealed films. This is much larger than the currently known limit (Fe65Co35 with Ms \sim 1900 emu/cm3). The present synthesis method can be used to develop writer materials for future magnetic recording application.

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Nian Ji, Valeria Lauter, Hailemariam Ambaye, Xiaowei Zhang, Sarbeswar Sahoo, Mike Kautzky, Mark Kief, Jian-Ping Wang. 2012-11-02. Polarized neutron reflectometry study of Fe16N2 with Giant Saturation Magnetization prepared by N Inter-diffusion in Annealed Fe-N Thin Films. https://arxiv.org/abs/1211.0551

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