Electrical control of hole spin relaxation in charge tunable InAs/GaAs quantum dots.
We report on optical orientation of singly charged excitons (trions) in charge-tunable self-assembled InAs/GaAs quantum dots. When the charge varies from 0 to -2, the trion photoluminescence of a single quantum dot shows up and under quasiresonant excitation gets progressively polarized from zero to approximately 100%. This behavior is interpreted as the electric control of the trion thermalization process, which subsequently acts on the hole-spin relaxation driven in nanosecond time scale by the anisotropic electron-hole exchange. This is supported by the excitation spectroscopy and time-resolved measurements of a quantum dot ensemble.
Laurent
S
S
CNRS-Laboratoire de Photonique et Nanostructures, Route de Nozay, 91460 Marcoussis, France.
Eble
B
B
Krebs
O
O
Lemaître
A
A
Urbaszek
B
B
Marie
X
X
Amand
T
T
Voisin
P
P