1. Department of Physics and Centre for Computational
Science and Engineering, National University of Singapore, Singapore 117542, Republic of Singapore
2. Center
for Phononics and Thermal Energy Science, School of Physics Science
and Engineering, Tongji University, 200092 Shanghai, People’s Republic of China
3. Graphene
Research Center, National University of Singapore, Singapore 117542, Republic of Singapore
4. NUS
Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 117456, Republic of Singapore