Donor-acceptor-like behavior of electron-hole pair recombinations in low-dimensional (Ga,In)N/GaN systems

Abstract

We propose a model for the radiative recombination of electron-hole pairs in (Ga,In)N/GaN quantum objects, including huge internal electric fields and strong carrier localization. This model explains why the time decay of the photoluminescence keeps a constant nonexponential shape, while its time scale can be varied over several orders of magnitude. Instead of localized excitons, we consider an electron and a hole independently localized at sharp potential fluctuations, along two parallel sheets, forming a two-dimensional pseudo-donor-acceptor pair.