KALLIAKOS , Sokratis

We present an experimental and theoretical study of the size dependence of the coupling between electron–hole pairs and longitudinal-optical phonons in Ga1−xInxN/GaN-based quantum wells and quantum boxes. We found that the Huang–Rhys factor S, which determines the distribution of luminescence intensities between the phonon replicas and the...

We use the intense, 5-ns-long, excitation pulses provided by the fourth harmonic of a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser to induce a strong high-energy shift of the photoluminescence of a 7.8-nm-wide GaN/Al0.15Ga0.85N single quantum well. We follow the complex relaxation dynamics of the energy and of the intensity of this...

International audience

We analyze the room temperature photoluminescence properties of several multilayer stackings of GaN/AlN quantum dots. We report drastic differences of emission energies and linewidths between continuous wave and time-resolvedphotoluminescence experiments. In continuous wave experiments, the screening of internal electric fields by accumulation...

The time dependence of the photoluminescence of GaN/AlN quantum dots (QD's) after high photoexcitation is examined on a large time scale. A continuous change in energy peak is reported, resulting in a giant energy shift of more than 1 eV after delays of several hundreds of microseconds. Simultaneously, the intensity decreases over more than...