S. W. Koch

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Fully microscopic models are used to calculate the carrier losses due to spontaneous emission and Auger recombination in semiconductor lasers. It is shown that the theory gives excellent agreement with the experiment using only basic experimental input and standard material parameters. The density dependence as assumed in semi-empirical approaches for(More)
To analyze experimental results in group-III nitride lasers, it is necessary to be able to predict their gain spectra accurately. Both excitons and electron hole plasma play important roles in the optical properties of group-III nitride compounds, even under typical lasing conditions of high carrier density and high temperature. Also, inhomogeneous(More)
In this paper, we illustrate the role of modeling in the development of commercial nitride-based lasers and LEDs. Aside from optimizing device performance, joint analysis of simulations and experimental results can shed light into the intrinsic properties of the InGaN/GaN material system.
A quantitative analysis of carrier and LO phonon scattering is presented. For quantification of scattering, effective times for carrier-carrier and carrier-phonon scattering are extracted from a microscopic calculation for different structures. A large variance is observed depending on the material parameters, sometimes providing counter-examples to(More)
Radiative losses of laser structures have been investigated using the semiconductor luminescence equations. This microscopic theory allows to predict losses due to spontaneous emission for structures without empirical fit parameters and using as input only the structural design and basic band structure parameters. The strength of radiative losses varies(More)
G. Blume Fachbereich Physik und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg, Germany and Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, United Kingdom A. Thränhardt, C. Schlichenmaier, P. J. Klar, G. Weiser, and S. W. Koch Fachbereich Physik und Wissenschaftliches(More)
This study developed a microscopic laser theory with predictive character which can be used in principle for nonequilibrium calculations. However, due to the high expense in calculation time, it is not applicable for parameter studies or the modelling of laser switch-on. Thus, this work developed a procedure of extracting effective scattering rates from(More)
Gain properties of GaInNAs lasers with different nitrogen concentrations in the quantum wells are investigated experimentally and theoretically. Whereas nitrogen incorporation induces appreciable modifications in the spectral extension and the carrier density dependence of the gain, it is found that the linewidth enhancement factor is reduced by inclusion(More)
B. Pasenow,1,2 C. Dineen,1,2 J. Hader,2,3 M. Brio,1 J. V. Moloney,1,2,* S. W. Koch,2,4 S. H. Chen,5,† A. Becker,5 and A. Jaroń-Becker5 1Arizona Center for Mathematical Sciences, Department of Mathematics, University of Arizona, Tucson, Arizona 85721, USA 2College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA 3Nonlinear Control(More)
(GaIn)(NAs) lasers of different material compositions are considered with respect to their gain properties and radiative and Auger losses. Scattering and dephasing processes are included on a microscopic basis. The theory shows good agreement to experiment. Optical properties for a 1.55 mum structure are investigated and show no principal degradation as(More)
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