Difference of self-energy corrections for charged and uncharged states in degenerate two dimensional systems

We study the Landau level fan diagram for charged and uncharged states in n-type modulation doped quantum wells with photoluminescence (PL) and photoluminescence excitation (PLE) measurements. In magnetic fields, the adjacent peak distance is different for PL and PLE. The peak energy for PL oscillates periodically in inverse magnetic fields while the peak energy for PLE does not oscillate. Time resolved PL shows that the difference of adjacent peak distance in PL and PLE is due to the hole relaxation and breaking of the transition selection rule. Within the experimental resolution, we attribute the different oscillatory behavior of the PL and PLE peak energies to different self-energy corrections for charged and uncharged states.