Detalhes bibliográficos
| Resumo: | We present a unified description of the excitonic properties of four monolayer transition-metal dichalcogenides (TMDC's) using an equation of motion method for deriving the Bethe-Salpeter equation in momentum space. Our method is able to cope with both continuous and tight-binding Hamiltonians, and is less computational demanding than the traditional first-principles approach. We show that the role of the exchange energy is essential to obtain a good description of the binding energy of the excitons. The exchange energy at the $\Gamma-$point is also essential to obtain the correct position of the C-exciton peak. Using our model we obtain a good agreement between the Rydberg series measured for WS$_2$. We discuss how the absorption and the Rydberg series depend on the doping. Choosing $r_0$ and the doping we obtain a good qualitative agreement between the experimental absorption and our calculations for WS$_2$. We also derive a semi-analytical version of Ellitot's formula for TMDC's. |
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| Autores principais: | Chaves, A. J. |
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| Outros Autores: | Ribeiro, R. M.; Frederico, T.; Peres, N. M. R. |
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| Assunto: | Excitons TMD Bethe-Salpeter Dirac 2D materials transition metal dichalcogenides Ciências Naturais::Ciências Físicas |
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| Ano: | 2017 |
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| País: | Portugal |
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| Tipo de documento: | artigo |
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| Tipo de acesso: | acesso aberto |
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| Instituição associada: | Universidade do Minho |
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| Idioma: | inglês |
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| Origem: | RepositóriUM - Universidade do Minho |
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