Metastable Polymorphic Phases in Monolayer TaTe2

Polymorphic phases and collective phenomena-such as charge density waves (CDWs)-in transition metal dichalcogenides (TMDs) dictate the physical and electronic properties of the material. Most TMDs naturally occur in a single given phase, but the fine-tuning of growth conditions via methods such as m...

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Detalles Bibliográficos
Autores: Bernardo, Iolanda Di, Ripoll Sau, Joan, Silva-Guillén, Jose Ángel, Calleja, Fabián, Ayani, Cosme G., Miranda, Rodolfo, Canadell, Enric, Garnica, Manuela, Vázquez de Parga, Amadeo L.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/331425
Acceso en línea:http://hdl.handle.net/10261/331425
https://api.elsevier.com/content/abstract/scopus_id/85151689450
Access Level:acceso abierto
Palabra clave:TaTe2
Density functional theory
Molecular beam epitaxy (MBE)
Scanning tunneling microscopy
Transition metal dichalcogenides (TMDs)
Descripción
Sumario:Polymorphic phases and collective phenomena-such as charge density waves (CDWs)-in transition metal dichalcogenides (TMDs) dictate the physical and electronic properties of the material. Most TMDs naturally occur in a single given phase, but the fine-tuning of growth conditions via methods such as molecular beam epitaxy (MBE) allows to unlock otherwise inaccessible polymorphic structures. Exploring and understanding the morphological and electronic properties of new phases of TMDs is an essential step to enable their exploitation in technological applications. Here, scanning tunneling microscopy (STM) is used to map MBE-grown monolayer (ML) TaTe2 . This work reports the first observation of the 1H polymorphic phase, coexisting with the 1T, and demonstrates that their relative coverage can be controlled by adjusting synthesis parameters. Several superperiodic structures, compatible with CDWs, are observed to coexist on the 1T phase. Finally, this work provides theoretical insight on the delicate balance between Te…Te and Ta-Ta interactions that dictates the stability of the different phases. The findings demonstrate that TaTe2 is an ideal platform to investigate competing interactions, and indicate that accurate tuning of growth conditions is key to accessing metastable states in TMDs.