Thin Ge layers deposited on Si(105) form a stable single-domain film structure with large terraces and rebonded-step surface termination, thus realizing an extended and ordered Ge/Si planar hetero-junction. At the coverage of four Ge monolayers angle-resolved photoemission spectroscopy reveals the presence of two-dimensional surface and film bands displaying energy-momentum dispersion compatible with the 5x4 periodicity of the system. The good agreement between experiment and first-principles electronic structure calculations confirms the validity of the rebonded-step structural model. The direct observation of surface features within 1 eV below the valence band maximum corroborates previously reported analysis of the electronic and optical behavior of the Ge/Si hetero-interface.
@article{arxiv.2307.01604,
title = {Electronic structure of the Ge/Si(105) hetero-interface},
author = {Polina M. Sheverdyaeva and Conor Hogan and Anna Sgarlata and Laura Fazi and Massimo Fanfoni and Luca Persichetti and Paolo Moras and Adalberto Balzarotti},
journal= {arXiv preprint arXiv:2307.01604},
year = {2023}
}