1. Technische Universität Dresden, 01062 Dresden, Germany
2. Leibnitz-Insitute for Crystal Growth, 12489 Berlin, Germany
3. RB Annis School of Engineering, University of Indianapolis, Indianapolis, Indiana 46227, USA
4. Simulation IT, Texas Tech Health Sciences Center, Lubbock Texas 79430-8317, USA
5. Physics Department, Texas Tech University, Lubbock Texas 79409-1051, USA