Passivation of Bi2Te3 Topological Insulator by Transferred CVD-Graphene: Toward Intermixing-Free Interfaces

The investigation, and ultimate application, of topological insulators, typically involve exposure to ambient conditions or their integration with metals, which lead to surface oxidation or material intermixing. X-ray photoelectron spectroscopy (XPS) measurements that demonstrate passivated and inte...

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Detalles Bibliográficos
Autores: Galceran, Regina, Bonell, Fréderic, Camosi, Lorenzo, Sauthier, Guillaume, Gebeyehu, Zewdu M., Esplandiú, María J., Arrighi, Aloïs, Fernández Aguirre, Iván, Figueroa, Adriana I., Sierra, Juan F., Valenzuela, Sergio O.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/295307
Acceso en línea:http://hdl.handle.net/10261/295307
Access Level:acceso abierto
Palabra clave:Bi2Te3
Graphene−topological insulator interface
Intermixing
Passivation
XPS
Descripción
Sumario:The investigation, and ultimate application, of topological insulators, typically involve exposure to ambient conditions or their integration with metals, which lead to surface oxidation or material intermixing. X-ray photoelectron spectroscopy (XPS) measurements that demonstrate passivated and intermixing-free interfaces in the topological insulator BiTe by means of dry-transferred CVD graphene are reported. After air exposure, no traces of BiTe oxidation are found. Furthermore, it is demonstrated that graphene acts as a very efficient metal and chalcogen diffusion barrier in BiTe/graphene/permalloy (Py) heterostructures, which are relevant for spintronics. Such results are in stark contrast with the significant surface degradation observed in bare BiTe under ambient conditions and the deep Bi-Te bonding disruption that occurs in BiTe/Py heterostructures. These findings provide a new approach to control and engineer topological insulator interfaces for spintronic applications and a new platform to investigate the combined use of graphene and topological insulator Dirac states.