1. Solid State Physics Department, University of Mazandaran, 47416-95447 Babolsar, Iran
2. Department of Physics, Institute for Advanced Studies in Basic Sciences, Zanjan 45137-66731, Iran
3. Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, 6708 WG Wageningen, The Netherlands
4. Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran, Iran