1. Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, #08-03, Innovis, Singapore 138634
2. LUMINOUS! Center of Excellence for Semiconductor Lighting and Displays, The Photonics Institute, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798
3. Bilkent University UNAM - Institute of Nanotechnology and Materials Science, Department of Electrical and Electronic Engineering, Department of Physics, Bilkent University, Ankara 06800, Turkey