1. Department of Electrical and Electronics Engineering, BITS Pilani, Hyderabad Campus, Hyderabad 500078, India
2. Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, A.P. 1-1010, Querétaro, Qro CP 76000, México
3. Materials Center for Sustainable Energy & Environment, Birla Institute of Technology and Science Pilani, Hyderabad Campus, Hyderabad 500078, India