P. Kossacki et al., Neutral and positively charged excitons: A magneto-optical study of a p-doped Cd1-xMnxTe quantum well, PHYS REV B, 60(23), 1999, pp. 16018-16026
We present a systematic study of optical transitions in a modulation doped
Cd1-xMnxTe quantum well with variable concentration of the hole gas. Using
a semimagnetic semiconductor as the quantum well material allowed us to con
trol independently the total hole concentration and its distribution betwee
n the two spin subbands (by a small magnetic field). Therefore, in transmis
sion experiment we analyze population effects and distinguish the influence
of spin-independent effects (screening) from spin-dependent ones (phase-sp
ace filling and intensity stealing). The observed variation of the exciton
(X) and charged exciton (X+) oscillator strengths can be accounted for assu
ming that the influence of phase-space filling is negligible and the variat
ion of oscillator strength due to screening is found to be similar for both
exciton species. We also show that the X+ dissociation energy significantl
y increases with the population of preexisting carriers with the appropriat
e spin. [S0163-1829(99)09147-X].