1. Electrical
Engineering Department, University of California at Los Angeles, Los Angeles, California 90095, United States
2. Department
of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
3. Department
of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
4. King Abdulaziz City for Science and Technology, Riyadh 11442, Saudi Arabia