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Reconstructions of the As-Terminated GaAs(001) Surface Exposed to Atomic Hydrogen.

ABSTRACT: We explore the atomic structures and electronic properties of the As-terminated GaAs(001) surface in the presence of hydrogen based on ab initio density functional theory. We calculate a phase diagram dependent on the chemical potentials of As and H, showing which surface reconstruction is the most stable for a given set of chemical potentials. The findings are supported by the calculation of energy landscapes of the surfaces, which indicate possible H bonding sites as well as the density of states, which show the effect of hydrogen adsorption on the states near the fundamental band gap.

SUBMITTER: Karmo M

PROVIDER: S-EPMC8851457 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Reconstructions of the As-Terminated GaAs(001) Surface Exposed to Atomic Hydrogen.

Karmo Marsel M Ruiz Alvarado Isaac Azahel IA Schmidt Wolf Gero WG Runge Erich E

ACS omega 20220203 6

We explore the atomic structures and electronic properties of the As-terminated GaAs(001) surface in the presence of hydrogen based on ab initio density functional theory. We calculate a phase diagram dependent on the chemical potentials of As and H, showing which surface reconstruction is the most stable for a given set of chemical potentials. The findings are supported by the calculation of energy landscapes of the surfaces, which indicate possible H bonding sites as well as the density of sta ...[more]

PMID: 35187322

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