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arXiv · 1906.06933

Lattice vibrations and electronic properties of GaSe nanosheets from first principles

Mousa Bejani·Olivia Pulci·Jamal Barvestani·Ali Soltani Vala·Friedhelm Bechstedt·Elena Cannuccia
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Abstract

Electronic properties and lattice dynamics of bulk $\varepsilon$-GaSe and mono-, bi- and tri-tetralayer GaSe are investigated by means of density functional and density functional perturbation theory. The few-tetralayers systems are semiconductors with an indirect nature of the fundamental band gap and a Mexican-hat-shape is observed at the top of the valence band. The phonon branches analysis reveals the dynamical stability for all systems considered together with the LO-TO splitting breakdown in two-dimensional systems. In-plane (E) and out-of-plane (A) zone-center lattice vibrations dominate the Raman and IR spectra.

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Mousa Bejani, Olivia Pulci, Jamal Barvestani, Ali Soltani Vala, Friedhelm Bechstedt, Elena Cannuccia. 2019-06-17. Lattice vibrations and electronic properties of GaSe nanosheets from first principles. https://doi.org/10.1103/physrevmaterials.3.124003

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