Large anisotropic spin relaxation time of exciton bound to donor states in triple quantum wells

Autor(es)

Ullah, S. ; Gusev, G. M. ; Bakarov, A. K. ; Hernandez, F. G. G.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Physics; v. 121, n. 20 MAY 28 2017.
• Citações Web of Science: 3

Resumo

We have studied the spin dynamics of a dense two-dimensional electron gas confined in a GaAs/AlGaAs triple quantum well by using time-resolved Kerr rotation and resonant spin amplification. Strong anisotropy of the spin relaxation time up to a factor of 10 was found between the electron spins oriented in-plane and out-of-plane when the excitation energy is tuned to an exciton bound to neutral donor transition. We model this anisotropy using an internal magnetic field and the inhomogeneity of the electron g-factor. The data analysis allows us to determine the direction and magnitude of this internal field in the range of a few mT for our studied structure, which decreases with the sample temperature and optical power. The dependence of the anisotropic spin relaxation was directly measured as a function of several experimental parameters: excitation wavelength, sample temperature, pump-probe time delay, and pump power. Published by AIP Publishing. (AU)

• Processo FAPESP: 15/16191-5 - Pesquisas em novos materiais envolvendo campos magnéticos intensos e baixas temperaturas
• Beneficiário: Gennady Gusev
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/03450-7 - O efeito Hall de spin em semicondutores
• Beneficiário: Felix Guillermo Gonzalez Hernandez
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/15007-5 - Dinâmica do magnetismo em nanocristais semicondutores
• Beneficiário: Felix Guillermo Gonzalez Hernandez
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 14/25981-7 - Geração e mapeamento espacial e temporal de correntes de spin
• Beneficiário: Felix Guillermo Gonzalez Hernandez
• Linha de fomento: Auxílio à Pesquisa - Regular