  We have mesured the carrier recombination dynamics in InGaN/GaN multiple
quantum wells over an unprecedented range in intensity. We find that at times
shorter than 30\,ns, they follow an exponential form, and a power law at times
longer than 1\,$\mu$s. To explain these biphasic dynamics, we propose a simple
three-level model where a charge-separated state interplays with the radiative
state through charge transfer following a tunneling mechanism. We show how the
distribution of distances in charge-separated states controls the dynamics at
long time. Our results imply that charge recombination happens on
nearly-isolated clusters of localization centers.
