[1
]Interdisciplinary
Graduate School, Nanyang Technological University, Singapore 639798
[2
]Energy
Research Institute @ NTU (ERI@N), Nanyang Technological University, 50 Nanyang
Drive, Singapore 637553
[3
]Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences,
Nanyang Technological University, 21 Nanyang Link, Singapore 637371
[4
]Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University,
Singapore 637371