1. Department of Physics, Izmir Institute of Technology, TR-35430 Izmir, Turkey.
2. Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA.
3. Physics Division, Illinois Institute of Technology, Chicago, IL 60616, USA.
4. Nuclear Engineering Division, Argonne National Laboratory, Argonne, IL 60439, USA.
5. Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8568, Japan.