Vertical Quantum Confinement in Bulk MoS2

We experimentally observe quantum confinement states in bulk MoS2 by using angle-resolved photoemission spectroscopy (ARPES). The band structure at the Gamma point reveals quantum well states (QWSs) linked to vertical quantum confinement of the electrons, confirmed by the absence of dispersion in k...

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Detalhes bibliográficos
Autores: Obando Guevara, Jairo, González García, Álvaro, Rosmus, Marcin, Olszowska, Natalia, González Barrio, Miguel Ángel, González Pascual, César, Tejeda, Antonio, Mascaraque Susunaga, Arantzazu
Formato: artículo
Fecha de publicación:2025
País:España
Recursos:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/118180
Acesso em linha:https://hdl.handle.net/20.500.14352/118180
Access Level:acceso embargado
Palavra-chave:538.9
Multilayer semiconductor
Two-dimensional material
Quantum well states
Band structure
Angle-resolved photoemission spectroscopy
Física del estado sólido
2211 Física del Estado Sólido
Descrição
Resumo:We experimentally observe quantum confinement states in bulk MoS2 by using angle-resolved photoemission spectroscopy (ARPES). The band structure at the Gamma point reveals quantum well states (QWSs) linked to vertical quantum confinement of the electrons, confirmed by the absence of dispersion in k z and a strong intensity modulation with the photon energy. Notably, the binding energy dependence of the QWSs versus n does not follow the quadratic dependence of a two-dimensional electron gas. Instead, a linear behavior is observed that is consistent with a parabolic-like quantum well. This confinement arises from the mechanical exfoliation preparation method, which leads to the detachment of a multilayer stack from the underlying bulk. This is confirmed by density functional theory (DFT) calculations. The quantum confinement in bulk-like MoS2 not only offers the opportunity to explore intersubband transitions to exploit optical properties but also provides a means to study fundamental quantum phenomena in multilayer stacks of different thicknesses.