Optical Signatures of Defect Centers in Transition Metal Dichalcogenide Monolayers

Even the best quality 2D materials have non-negligible concentrations of vacancies and impurities. It is critical to understand and quantify how defects change intrinsic properties, and use this knowledge to generate functionality. This challenge can be addressed by employing many-body perturbation...

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Detalles Bibliográficos
Autores: Melo, Pedro Miguel M. C. de, Zanolli, Zeila, Verstraete, Matthieu J.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/265511
Acceso en línea:http://hdl.handle.net/10261/265511
Access Level:acceso abierto
Palabra clave:Defect centers
Optical absortion
Transition metal dichalcogenides
Quantum dots
Descripción
Sumario:Even the best quality 2D materials have non-negligible concentrations of vacancies and impurities. It is critical to understand and quantify how defects change intrinsic properties, and use this knowledge to generate functionality. This challenge can be addressed by employing many-body perturbation theory to obtain the optical absorption spectra of defected transition metal dichalcogenides. Herein metal vacancies, which are largely unreported, show a larger set of polarized excitons than chalcogenide vacancies, introducing localized excitons in the sub-optical-gap region, whose wave functions and spectra make them good candidates as quantum emitters. Despite the strong interaction with substitutional defects, the spin texture and pristine exciton energies are preserved, enabling grafting and patterning in optical detectors, as the full optical-gap region remains available. A redistribution of excitonic weight between the A and B excitons is visible in both cases and may allow the quantification of the defect concentration. This work establishes excitonic signatures to characterize defects in 2D materials and highlights vacancies as qubit candidates for quantum computing.