1. Department of Physics, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India
2. Department of Mechanical Engineering and Material Science, Rice University, Houston, Texas 77005, United States
3. Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, National Physical Laboratory, New Delhi 110012, India
4. Centre for NanoBioengineering & Spin Tronics, Chungnam National University, 220 Gung-Dong Yuseong-Gu, Daejeon 305-764, Korea
5. Department of Biotechnology, Delhi Technological University, Delhi 11042, India