Affiliation: | 1. Department of Physics, Karunya University, Coimbatore 641 114, Tamilnadu, India;2. Department of Physics, United Institute of Technology, Coimbatore, India;3. Department of Electrical and Computer Engineering, Ajou University, Suwon 443-749, South Korea;4. Department of Physics, P.S.G. College of Arts and Science, Coimbatore 641 014, Tamilnadu, India |