Spectroscopic properties of few-layer tin chalcogenides

Stable structures of layered SnS and SnSe and their associated electronic and vibrational spectra are predicted using first-principles DFT calculations. The calculations show that both materials undergo a phase transformation upon thinning whereby the in-plane lattice parameters ratio a/b converges...

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Detalles Bibliográficos
Autores: Dewandre, Antoine, Verstraete, Matthieu J.|||0000-0001-6921-5163, Grobert, Nicole, Zanolli, Zeila|||0000-0003-0860-600X
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:232370
Acceso en línea:https://ddd.uab.cat/record/232370
https://dx.doi.org/urn:doi:10.1088/2515-7639/ab3513
Access Level:acceso abierto
Palabra clave:Monochalcogenides
Electronic structure
Raman spectroscopy
2D materials
Nanomaterials
Dielectric response
Descripción
Sumario:Stable structures of layered SnS and SnSe and their associated electronic and vibrational spectra are predicted using first-principles DFT calculations. The calculations show that both materials undergo a phase transformation upon thinning whereby the in-plane lattice parameters ratio a/b converges towards 1, similar to the high-temperature behaviour observed for their bulk counterparts. The electronic properties of layered SnS and SnSe evolve to an almost symmetric dispersion whilst the gap changes from indirect to direct. Characteristic signatures in the phonon dispersion curves and surface phonon states where only atoms belonging to surface layers vibrate should be observable experimentally.