| Full text | |
| Author(s): |
Ullah, S.
[1, 2]
;
Moraes, F. C. D.
[1]
;
Gusev, G. M.
[1]
;
Bakarov, A. K.
[3, 4]
;
Hernandez, F. G. G.
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Sao Paulo, Inst Fis, Caixa Postal 66318, BR-05315970 Sao Paulo, SP - Brazil
[2] Gomal Univ, Dept Phys, Dera Ismail Khan 29220, KP - Pakistan
[3] Novosibirsk State Univ, Novosibirsk 630090 - Russia
[4] Inst Semicond Phys, Novosibirsk 630090 - Russia
Total Affiliations: 4
|
| Document type: | Journal article |
| Source: | Journal of Applied Physics; v. 123, n. 21 JUN 7 2018. |
| Web of Science Citations: | 0 |
| Abstract | |
We address the temperature influence on the precessional motion of electron spins under a transverse magnetic field, studied in GaAs/AlGaAs triple quantum wells, using pump-probe Kerr rotation. In the presence of an applied in-plane magnetic field, the TRKR measurements show the robustness of carrier's spin polarization against temperature, which can be easily traced in an extended range up to 250 K. By tuning the pump-probe wavelength to the exciton bound to a neutral donor transition, we observed a remarkably long-lasting spin coherence (with dephasing time T-2({*}) > 14 ns) limited by the spin hopping process and exchange interaction between the donor sites, as well as the ensemble spread of the g-factor. The temperature dependent spin dephasing time revealed a double linear dependence due to the different relaxation mechanisms active in respective temperature ranges. We observed that the increase in sample temperature from 5 K to 250 K leads to a strong T-2({*}) reduction by almost 98%/97% for the excitation wavelengths of 823/821 nm. Furthermore, we noticed that the temperature increase not only causes the reduction of spin lifetime, but can also lead to the variation of the electron g-factor. Additionally, the spin dynamics were studied through the dependencies on the applied magnetic field and optical pump power. Published by AIP Publishing. (AU) | |
| FAPESP's process: | 14/25981-7 - Generating and mapping spin currents with space and time resolution |
| Grantee: | Felix Guillermo Gonzalez Hernandez |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 15/16191-5 - The research in new materials involving high magnetic fields and low temperatures |
| Grantee: | Gennady Gusev |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 09/15007-5 - Magnetic dynamics in semiconductor nanocrystals |
| Grantee: | Felix Guillermo Gonzalez Hernandez |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 13/03450-7 - The spin Hall effect in semiconductors |
| Grantee: | Felix Guillermo Gonzalez Hernandez |
| Support Opportunities: | Regular Research Grants |