1. Department of Electrical and Electronics Engineering Department of Physics UNAM – Institute of Materials Science and Nanotechnology Bilkent University Ankara 06800 Turkey
2. LUMINOUS! Centre of Excellence for Semiconductor Lighting and Displays The Photonics Institute School of Electrical and Electronic Engineering School of Physical and Mathematical Sciences School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore
3. Department of Materials Science and Nanotechnology Abdullah Gul University Kayseri 38080 Turkey