SHAKEUP PROCESSES IN THE RECOMBINATION SPECTRA OF NEGATIVELY CHARGED EXCITONS

We report on shakeup processes in the luminescence spectra of a negati vely charged exciton (X(-)) at moderate magnetic fields. These process es manifest themselves as a series of low-energy satellite peaks emerg ing from the negatively charged exciton line. We analyze the dependenc e of the X(-) energy on magnetic field. We conclude that at magnetic f ields above similar to 1 T the X(-) structure can be viewed as an elec tron at the lowest Landau level bound to an exciton.