Energy levels of negatively charged excitons in high magnetic fields

We have studied the photoluminescence energy of the negatively charged exciton for different polarisations in a 100 إ GaAs/AlGaAs quantum well in magnetic fields up to 50 T. By observing recombination from all of the optically active singlet and triplet states of the charged exciton, we have experimentally determined its energy level diagram.