Many-body Complex Research Articles

Correlation energies of many-body complexes in biased InAs/GaAs quantum dots

The aim of this work is to analyze theoretically the correlation energies for neutral, positively, negatively charged exciton and bi-exciton. So, we propose a model consistent with experimental observations that is small InAs truncated pyramids with circular base lying on wetting layer, both buried into GaAs matrix. In a first step and in contrast to other works, we are able to evaluate coulombic interactions between electron and hole, two electrons and two holes by perturbative method at the second order. In a second step, the correlation energies of many-body complexes X, X - , X + and XX are investigated as a function of quantum dots basis radius r c and the applied electric field. Our main goal is to provide realistic estimation for the correlation energies of excitons, charged excitons and bi-excitons while retaining at the same time a transparent formalism, which could easily be transposed to structures of actual interest. The present work provides evidence of the stability of excitons, charged excitons and bi-excitons in InAs/GaAs quantum dots. Calculated correlation energies of many-body complexes are consistent with those reported by recent photoluminescence measurements.

Study of correlation effects on stability of many-body complexes in III–V nitride quantum dots

The aim of this work is to analyze theoretically the correlation energies, for neutral, positive and negative excitons and bi-excitons in the III–V nitride In x Ga 1− x N/GaN quantum dot; where x=17.5% denotes the indium concentration. So, we propose a model consistent with experimental observations that is small In x Ga 1− x N truncated pyramids with circular base lying on wetting layer, both buried into GaN matrix. The correlation energies of many-body complexes X, X −, X + and XX are investigated as a function of the quantum dot radius r c and the intrinsic electric field.

Studies of complex systems: from atoms to clusters

We have investigated with unprecedented levels of detail fundamental studies of dynamical processes and structure of few- and many-body complex systems at the atomic, molecular, and cluster level. This was achieved using inner-shell photodetachment and photoionization experiments using photoion, photoelectron, resonant Auger, resonant Raman Auger and electron-spin resolved experimental techniques coupled with the brightness, spectral resolution, and polarization of the Advanced Light Source at Lawrence Berkeley National Laboratory. The experimental results, which revealed new phenomena, are pushing the limits of third generation photon sources and are stimulating various enhanced theories.

Dielectronic recombination of N^{4+}

The dielectronic recombination spectrum of ${\mathrm{N}}^{4+}$ has been measured with high resolution and accuracy. The ${1s}^{2}2p5l$ resonances in the energy range $0--1.6\mathrm{eV}$ were studied in detail. The experimental spectrum is compared with the results from four different calculations. An almost perfect agreement between the experiment and a calculation which combines relativistic many-body perturbation theory and complex rotation is found. The calculation provides accurate spectroscopic data for all fifty ${1s}^{2}2p5l$ states. The literature value for the ${1s}^{2}2p5s$ ${}^{1}P$ energy level is found to be off by more than 0.1 eV.