Affiliation: | a Ankara University, Faculty of Science, Department of Physics, Tando?an-Ankara 06100, Turkey b Department of Electrical and Electronics Engineering, Ba?kent University, Ba?l?ca Campus Eski?ehir Yolu 20. Km, Ba?l?ca, 06530 Ankara, Turkey c Science and Arts Faculty, Department of Physics, Kirikkale University, Yah?ihan Kampus, Kirikkale, Turkey |