Polarized fine structure in the photoluminescence excitation spectrum of a negatively charged quantum dot.
We report polarized photoluminescence excitation spectroscopy of the negative trion in single charge-tunable quantum dots. The spectrum exhibits a p-shell resonance with polarized fine structure arising from the direct excitation of the electron spin triplet states. The energy splitting arises from the axially symmetric electron-hole exchange interaction. The magnitude and sign of the polarization are understood from the spin character of the triplet states and a small amount of quantum dot asymmetry, which mixes the wave functions through asymmetric e-e and e-h exchange interactions.
Ware
M E
ME
Naval Research Laboratory, Washington, DC 20375, USA.
Stinaff
E A
EA
Gammon
D
D
Doty
M F
MF
Bracker
A S
AS
Gershoni
D
D
Korenev
V L
VL
Bădescu
S C
SC
Lyanda-Geller
Y
Y
Reinecke
T L
TL