1. Gebze Technical University,Physics Department,Gebze/Kocaeli,Turkey,41400
2. Institute of Nanotechnology, Gebze Technical University,Gebze/Kocaeli,Turkey,41400
3. Marmara University,Department of Physics,Göztepe-Istanbul,Turkey,81040
4. Kazan State Power Engineering University,Kazan/Tatarstan,Russian Federation,420066