Time-resolved photoluminescence in the fractional quantum Hall regime

Photoluminescence (PL) spectra from excitons in the 2D electron layer in GaAs shows anomalous behavior that reflects the intrinsic properties of the strongly interacting 2D electron system. In the regime of the fractional quantum Hall effect an additional spectral peak is observed for Landau filling factor v< 1 2. At v = 1 3 a dramatic transfer of intensity between the peaks is observed which is coincident with a sharp increase in the PL decay times. This effect is influenced by changes in electron-hole overlap as a result of changes in the polarizability of the Laughlin fluid/electron gas. In the extreme quantum limit v< 1 4, the PL decay time for the higher-energy peak decreases while the lower-energy peak decay time increases.