R. Rapaport et al., Density dependent coupling of negatively charged excitons with confined photons in a GaAs/AlAs microcavity, PHYS ST S-A, 178(1), 2000, pp. 481-487
The negatively charged exciton (X-) is observed to strongly couple with the
microcavity (MC)-confined photons in a GaAs quantum well containing a two-
dimensional electron gas with 0 < n(e) < 3 x 10(10) cm(-2). This strong cou
pling results in the formation of charged polaritons. The coupling strength
is found to depend on root n(c), in analogy to two-level atoms in a cavity
. A model is suggested to explain this dependence. The analysis of the refl
ection and photoluminescence spectra shows that X- is strongly admired with
the neutral exciton (X) via their coupling with the MC-photons. The linewi
dth dependence on n(e) indicates that electron-polariton scattering is effe
ctive.