1. Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
2. Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
3. Semiconsultants, Brunnsgrnd 12, SE-18773 Täby, Sweden
4. School of Electrical Engineering, University of Belgrade, Belgrade 11120, Serbia
5. Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-Ku, Sendai, Japan
6. Laboratory for Electro-Optics Systems, Indian Space Research Organization, Bangalore 560058, India