1. The Kotel'nikov Institute of Radioengineering and Electronics of Russian Academy of Sciences; Vvedensky square 1 141120 Fryazino Moscow Region Russia
2. Department of Physics; Arab American University-Jenin; PO Box 240 Jenin Palestinian Territories
3. Laboratory of Micro- and PhotonElectronics; Dept. of Electronics and Informatics; Vrije Universiteit Brussel; Pleinlaan 2 1050 Brussels Belgium