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arXiv · 1702.01509

Thickness-dependent electronic and magnetic properties of $γ'$-Fe$_{\mathrm 4}$N atomic layers on Cu(001)

Y. Takahashi·T. Miyamachi·S. Nakashima·N. Kawamura·Y. Takagi·M. Uozumi·V. Antonov·T. Yokoyama·A. Ernst·F. Komori
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Abstract

Growth, electronic and magnetic properties of $γ'$-Fe$_{4}$N atomic layers on Cu(001) are studied by scanning tunneling microscopy/spectroscopy and x-ray absorption spectroscopy/magnetic circular dichroism. A continuous film of ordered trilayer $γ'$-Fe$_{4}$N is obtained by Fe deposition under N$_{2}$ atmosphere onto monolayer Fe$_{2}$N/Cu(001), while the repetition of a bombardment with 0.5 keV N$^{+}$ ions during growth cycles results in imperfect bilayer $γ'$-Fe$_{4}$N. The increase in the sample thickness causes the change of the surface electronic structure, as well as the enhancement in the spin magnetic moment of Fe atoms reaching $\sim$ 1.4 $μ_{\mathrm B}$/atom in the trilayer sample. The observed thickness-dependent properties of the system are well interpreted by layer-resolved density of states calculated using first principles, which demonstrates the strongly layer-dependent electronic states within each surface, subsurface, and interfacial plane of the $γ'$-Fe$_{4}$N atomic layers on Cu(001).

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Y. Takahashi, T. Miyamachi, S. Nakashima, N. Kawamura, Y. Takagi, M. Uozumi, V. Antonov, T. Yokoyama, A. Ernst, F. Komori. 2017-02-06. Thickness-dependent electronic and magnetic properties of $γ'$-Fe$_{\mathrm 4}$N atomic layers on Cu(001). https://doi.org/10.1103/physrevb.95.224417

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