Relation between Structural Parameters and the Effective Electron–Hole Separation in InGaN/GaN Quantum Wells

The photoluminescence (PL) of InGaN/GaN quantum well (QW) structures is measured as a function of biaxial strain to study the dependence of the luminescence emission on the built-in electric field. The direction and magnitude of the shift in luminescence energy with strain reveals an effective e-h separation in the well. We have used this method to evaluate the effective e-h separation in a number of structures with varying QW thickness and indium content. Our results show that the e-h separation increases with increasing QW thickness and with increasing indium content.