Yongquan Zeng1, Udvas Chattopadhyay2, Bofeng Zhu2, Bo Qiang1,2, Jinghao Li1, Yuhao Jin1, Lianhe Li3, Alexander Giles Davies3, Edmund Harold Linfield3, Baile Zhang2*, Yidong Chong2* & Qi Jie Wang1,2*
1 Centre for OptoElectronics and Biophotonics, School of Electrical and Electronic Engineering & The Photonics Institute, Nanyang Technological University, Singapore, Singapore.
2 Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
3 School of Electronic and Electrical Engineering, University of Leeds, Leeds, UK.
