1. Department of Physics and Astronomy, National Institute of Technology 1 , Rourkela, Odisha 769008, India
2. Department of Materials Science and Engineering, University of Tennessee 2 , Knoxville, Tennessee 37996, USA
3. Materials Research Laboratory, Department of Physics, Osmania University 3 , Hyderabad 500007, India
4. CSIR National Physical Laboratory 4 , Dr. K. S. Krishnan Marg, New Delhi 110012, India