Growth, electronic, and magnetic properties of ${\gamma }^{\prime }\text{−}{\mathrm{Fe}}_4\mathrm{N}$ 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 ${\gamma }^{\prime }\text{−}{\mathrm{Fe}}_4\mathrm{N}$ is obtained by Fe deposition under ${\mathrm{N}}_2$ atmosphere onto monolayer ${\mathrm{Fe}}_2\mathrm{N}/\mathrm{Cu}\left(001\right)$, while the repetition of a bombardment with 0.5 keV ${\mathrm{N}}^{+}$ ions during growth cycles results in imperfect bilayer ${\gamma }^{\prime }\text{−}{\mathrm{Fe}}_4\mathrm{N}$. The increase in the sample thickness causes the change in the surface electronic structure, as well as the enhancement in the spin magnetic moment of Fe atoms reaching $\sim 1.4{\mu }_{\mathrm{B}}/\mathrm{atom}$ in the trilayer sample. The observed thickness-dependent properties of the system are well interpreted by the 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 ${\gamma }^{\prime }\text{−}{\mathrm{Fe}}_4\mathrm{N}$ atomic layers on Cu(001).

• Received 6 February 2017
• Revised 2 May 2017

DOI:https://doi.org/10.1103/PhysRevB.95.224417