| Texto completo | |
| Autor(es): |
Guilhon, I.
;
Marques, M.
;
Teles, L. K.
;
Bechstedt, F.
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | PHYSICAL REVIEW B; v. 95, n. 3, p. 9-pg., 2017-01-10. |
| Resumo | |
The (BN)(1-x)(C2)(x) alloys are promising materials for band-gap engineering in two-dimensional electronics. In this work, we provide a complete scenario of statistical possibilities for the distribution of atoms and its influence on electronic and optical properties. Using first-principles calculations combined with the generalized quasichemical approximation to account for disorder effects, we study the properties of these two-dimensional alloys as a function of their average composition. Our results show that atomic arrangements with C-C and B-N bonds are energetically favored over the ones with B-B and N-N bonds, explaining the known tendency to phase separation, verified by a T-x phase diagram. We calculate the energy gap as a function of the composition considering both composition fluctuation and phase separation effects. Experimental data are discussed in this context. Finally, we obtain absorption spectra reproducing a two-peak pattern for intermediate carbon concentrations found experimentally and identified with phase-segregated instead of homogeneous alloys. (AU) | |
| Processo FAPESP: | 12/50738-3 - Estudo de pontos quânticos através de cálculos de primeiros princípios |
| Beneficiário: | Ronaldo Rodrigues Pelá |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |