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arXiv · 2307.01604

Electronic structure of the Ge/Si(105) hetero-interface

Polina M. Sheverdyaeva·Conor Hogan·Anna Sgarlata·Laura Fazi·Massimo Fanfoni·Luca Persichetti·Paolo Moras·Adalberto Balzarotti
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Abstract

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.

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Polina M. Sheverdyaeva, Conor Hogan, Anna Sgarlata, Laura Fazi, Massimo Fanfoni, Luca Persichetti, Paolo Moras, Adalberto Balzarotti. 2023-07-04. Electronic structure of the Ge/Si(105) hetero-interface. https://doi.org/10.1088/1361-648x/aae66f

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