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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Magnetic and power tuning of spin-asymmetric multiple excitons in a GaAs quantum well

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Naranjo, A. [1] ; Braganca, H. [1, 2] ; Jacobsen, G. M. [1] ; de Morais, R. R. O. [3] ; Quivy, A. A. [4] ; Marques, G. E. [1] ; Lopez-Richard, V [1] ; Teodoro, M. D. [1]
Total Authors: 8
[1] Univ Fed Sao Carlos, Dept Fis, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Brasilia, Inst Fis, BR-70919970 Brasilia, DF - Brazil
[3] Univ Fed Rondonopolis, Inst Ciencias Nat & Terra, BR-78735910 Rondonapolis, Mato Grosso - Brazil
[4] Univ Sao Paulo, Inst Phys, BR-05508090 Sao Paulo - Brazil
Total Affiliations: 4
Document type: Journal article
Web of Science Citations: 0

A comprehensive study of excitonic complexes in high-quality GaAs quantum wells has been performed. The polarization-resolved photoluminescence results show exciton, biexciton, and trion emissions tuned by temperature, excitation power, and by an external magnetic field. Excitons and biexcitons show important differences in their dependence on the external field. While the Zeeman splitting of biexcitons depends monotonically on the magnetic field, with a nearly constant gfactor, the behaviour of the exciton energy splitting is nonmonotonic and includes an inversion of sign as a function of the magnetic field. More importantly, we observe that a trion resonance emerges at a finite magnetic field, and only appears at low laser excitation power and for sigma(+) polarization emission. The non-trivial dependence of the energy levels on the external magnetic field, together with the polarization selective trion emission, leads to an intricate exciton and trion dynamics, which can be reproduced by a set of coupled rate equations. Based on this theoretical approach, we show that a fast spin-flip process can lead to the spinasymmetric emission, which reveals a contrasting spin-dynamics of excitonic complexes ruled by their charge. (AU)

FAPESP's process: 18/01914-0 - Functionalizing the optical emission in quantum tunneling nanostructures in different spectral intervals
Grantee:Marcio Daldin Teodoro
Support Opportunities: Regular Research Grants
FAPESP's process: 17/23668-8 - Many-body effects on Valley qubits and on the magneto-optical properties of transition metal dichalcogenide monolayers
Grantee:Helena de Souza Bragança Rocha
Support Opportunities: Scholarships in Brazil - Post-Doctoral
FAPESP's process: 13/18719-1 - Electronic carriers dynamics in semiconductor nanostructures
Grantee:Marcio Daldin Teodoro
Support Opportunities: Research Grants - Young Investigators Grants
FAPESP's process: 14/19142-2 - Characterization and processing of semiconductor nanostructures and application as devices
Grantee:Gilmar Eugenio Marques
Support Opportunities: Research Projects - Thematic Grants