We have examined the carrier capture dynamics and excitation dependent charge distributions of coupled InGaN/ GaN multiple quantum well samples. We measured the temporal evolution of time-delayed cathodoluminescence ͑CL͒ spectra to study the temperature-and excitation-dependent transfer of carriers from a surrounding confinement region into a coupled single quantum well. Samples possessing two different structures for the confinement region ͓i.e., number of quantum wells ͑QWs͒ and varying

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... ͔ were examined with CL. In order to study state filling of the SQW and QWs in the confinement region, we calculated the quasi-Fermi levels and carrier densities by utilizing a model that involves self-consistent solutions of the nonlinear Poisson-Schrödinger equation for wurtzite QWs including strain, deformation potentials, and polarization fields. Band-edge and effective mass parameters were first obtained from a strain-and In composition-dependent k · p calculation for wurtzite In x Ga 1−x N, using a 6 ϫ 6 k · p Hamiltonian in the ͕0001͖ representation. The model shows that the difference in the quasi-Fermi levels between the confinement and SQW regions decreases with increasing excitation and temperature. Likewise, a reversal in the relative magnitude of the carrier densities between these two regions occurs at a certain temperature and excitation. Furthermore, the results for the model describing the steady-state excitation are consistent with those for the transient excitation in time-resolved CL, which also exhibit a marked increase in the rate of carrier transfer to the SQW region as the temperature increases.