Palestrante
Descrição
Dynamics of differently spin-polarized photoexcited carriers was investigated by the time-resolved photoluminescence (PL) in a system of Landau levels (LL) formed in an InGaAs/InP quantum well. Oscillations of the ground state LL energy caused by the filling factor dependent screening of excitons were observed in both spin-up and spin-down polarizations. The obtained results are evidence of an insignificant spin-flip process in the InGaAs/InP quantum well. Shake-up emission from LLs above the Fermi level was observed and it was found to considerably affect the recombination dynamics of LLs. Particularly, the inter-LL scattering responsible for the shake-up effect manifests itself in a rapid decay of the emission from LLs.
PL transients revealed two characteristic times caused by recombination of two groups of photogenerated carriers which recombine independently. The inter-LL scattering is shown to be responsible for the time delay of PL response. The characteristic time about 200 ps of the inter-LL transitions was determined. The sharp minimum of the recombination time was found in the interval of the magnetic field where the transition between the quantum Hall phases with the filling factors ν=1 and ν=2 takes place; the recombination time minimum is attributed to the formation of the metallic intermediate phase which causes increasing overlap between the electron and hole wave functions. The main results were published in (1).
Referências
1 TEODORO, M. D. et al. Recombination dynamics of Landau levels in an InGaAs/InP quantum well. Physical Review B, v. 98, n. 15, p. 155431-1-155431-7, Oct. 2018.
| Subárea | Física da Matéria Condensada |
|---|---|
| Apresentação do trabalho acadêmico para o público geral | Não |
