M. Vennila - University of Madras
R. Rathikha - Presidency University
S. Muthu - Department of Physics, Arignar Anna Govt. Arts College, Cheyyar, 604 407, Tamil Nadu, India
A. Senthil - SRM Institute of Science and Technology
A. Jeelani - Department of Physics, Lakshmi Bangaru Arts and Science College, Melmaruvathur, 603319, Tamil Nadu, India
Ahmad Irfan - King Khalid University