1. State Key Laboratory of Material Processing and Die & Mould Technology
2. School of Materials Science and Engineering
3. Huazhong University of Science and Technology (HUST)
4. Wuhan 430074
5. P. R. China
6. Centre for Micro and Nano Devices
7. Department of Physics
8. COMSATS Institute of Information Technology
9. Islamabad 44000
10. Pakistan