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arXiv · 1503.02440

Quantized electronic fine structure with large anisotropy in ferromagnetic Fe films

C. Seibel·A. Nuber·H. Bentmann·M. Mulazzi·P. Blaha·G. Sangiovanni·F. Reinert
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Abstract

We report on the spectroscopic observation of a quantized electronic fine structure near the Fermi energy in thin Fe films grown on W(110). The quantum well states are detected down to binding energies of $\sim$10 meV by angle-resolved photoelectron spectroscopy. The band dispersion of these states is found to feature a pronounced anisotropy within the surface plane: It is free-electron like along the $\bar{\Gamma \rm{H}}$-direction while it becomes heavy along $\bar{\Gamma \rm{N}}$. Density functional theory calculations identify the observed states to have both majority and minority spin character and indicate that the large anisotropy can be dependent on the number of Fe-layers and coupling to the substrate.

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C. Seibel, A. Nuber, H. Bentmann, M. Mulazzi, P. Blaha, G. Sangiovanni, F. Reinert. 2015-03-09. Quantized electronic fine structure with large anisotropy in ferromagnetic Fe films. https://doi.org/10.1103/physrevb.90.035136

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