1. School of Electrical and Electronic Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore
2. Department of Materials Design and Innovation University at Buffalo The State University of New York Buffalo NY 14260 USA
3. Nano‐Convergence Mechanical Systems Research Division Korea Institute of Machinery and Materials 156, Gajeongbuk‐ro, Yuseong‐gu Daejeon 34103 South Korea