Joachim Piprek received his Diploma and Doctoral degrees in physics from Humboldt University in Berlin, Germany. For more than two decades, he worked in industry and academia on design, simulation, and analysis of various semiconductor devices used in optoelectronics. Dr. Piprek has taught graduate courses at universities in Germany, Sweden, and in the United States. He is founder and co-chair of the annual conference on Numerical Simulation of Optoelectronic Devices (NUSOD) and he also chaired several SPIE conferences. Dr. Piprek was invited guest editor for different special journal issues on optoelectronic device simulation and he currently serves as executive/associate editor of two research journals. He has published 4 books, 7 book chapters, and about 250 papers with more than 6500 citations.