1. Solid State Ionics and Luminescence Laboratory Department of Physics Bharathiar University Coimbatore India
2. Materials Research Centre Department of Physics N. G. M. College Coimbatore India
3. Herbert Gleiter Institute of Nanoscience Nanjing University of Science and Technology Nanjing China
4. Department of Physics Avinashilingam Institute for Home Science and Higher Education for Women Coimbatore India