Spin dynamics of excitons and magnetic ions in Cd1−Mn Te/Cd1−Mg Te quantum wells

Ultrafast exciton spin dynamics in Cd 1− x Mn x Te quantum wells studied by transient pump‐probe spectroscopy

“…In magnetic field of 3 T, the pump-probe excitonic bleaching peak shows single-exponential relaxation with time constant of 150 ps. These results indicates that the slow energy relaxation process observed in the pump-probe experiments with and without magnetic field is the localization effect of exciton due to the fluctuation of alloy composition in QWs [5]. The fast component of the energy relaxation is resulted from the EMP formation.…”

“…the reduction of linear absorption of excitons after the pump pulse excitation, results from the screening of Coulomb interaction among band carriers in the early delay time region and is due to the exciton bleaching after the e-h plasma decays [5][6][7]. The renormalized energy band-gap of the sample after an intense optical pump can be extracted as follows: The experimental spectra of linear optical density αd deduced from the spectra of transient absorption ∆αd are fitted by the calculated spectra which include the effects of Coulomb screening, band-gap renormalization and carrier heating [5]. In Fig.…”

Ultrafast spin injection from Cd1−Mn Te magnetic barriers into a CdTe quantum well studied by pump–probe spectroscopy

“…The period of the QW structure was 30. Pump-probe absorption spectroscopy was performed in magnetic fields [4,5]. The experimental set-up for the pump-probe measurement is described in detail elsewhere [6].…”

Transient photoluminescence spectroscopy of spin injection dynamics in double quantum wells of diluted magnetic semiconductors

“…However the time resolution of the streak camera system is not sufficient to clarify faster spin processes. For the purpose to resolve the faster spin dynamics, we employed the pump-and-probe transient absorption spectroscopy with the circular polarization analysis [7][8][9]. The sample used is a Cd 0.95 Mn 0.05 Te/Cd 0.75 Mg 0.25 Te quantum well (QW).…”