As an effort to investigate new techniques to reduce the effect of the strong internal polarization fields in (In,Ga)N/GaN quantum well (QW) structures we have studied the influence of inserting a thin wide band-gap AI(0 95)In(0.05)N interlayer inside the QWs, in order to modify the potential and increase the electron-hole overlap. A strong reduction of the decay times of the photoluminescence (PL) was observed in this case at all temperatures up to 300 K, without a strong reduction in PL intensity. The tunneling electron-hole transition across the interlayer is observed to be dominant at room temperature for high excitation conditions. (c) 2007 WILEYNCH Verlag GmbH & Co. KGaA, Weinheim.