1. Department of Computer Sciences and Microsystem Technology, University of Applied Sciences Kaiserslautern; Zweibrücken 66482 Germany
2. RAM Group DE GmbH; Zweibrücken 66482 Germany
3. Department of Physics, RWTH Aachen University; Sommerfeldstr. 14 52074 Aachen Germany
4. Department of Electrical Engineering and Information Technology, Institute for Materials in Electrical Engineering 1, RWTH Aachen University; Sommerfeldstr. 24 52074 Aachen Germany
5. ICTEAM Institute/Electrical Engineering, Université catholique de Louvain; Louvain la Neuve 1348 Belgium