Dielectric screening of excitons and trions in single-layer MoS2.
Nano Lett
; 14(10): 5569-76, 2014 Oct 08.
Article
em En
| MEDLINE
| ID: mdl-25216267
ABSTRACT
Photoluminescence (PL) properties of single-layer MoS2 are indicated to have strong correlations with the surrounding dielectric environment. Blue shifts of up to 40 meV of exciton or trion PL peaks were observed as a function of the dielectric constant of the environment. These results can be explained by the dielectric screening effect of the Coulomb potential; based on this, a scaling relationship was developed with the extracted electronic band gap and exciton and trion binding energies in good agreement with theoretical estimations. It was also observed that the trion/exciton intensity ratio can be tuned by at least 1 order of magnitude with different dielectric environments. Our findings are helpful to better understand the tightly bound exciton properties in strongly quantum-confined systems and provide a simple approach to the selective and separate generation of excitons or trions with potential applications in excitonic interconnects and valleytronics.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Substâncias Luminescentes
/
Dissulfetos
/
Molibdênio
Tipo de estudo:
Diagnostic_studies
/
Screening_studies
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article