1. Laboratoire Lumière, nanomatériaux et nanotechnologie, CNRS UMR 7076, Université de Technologie de Troyes, BP 2060, 10010 Troyes, France
2. Department of Physics, Hanyang University, Seoul 04763, Republic of Korea
3. Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea
4. Département de Génie Electrique, Ecole Nationale Supérieure d’Ingénieurs (ENSI), Université de Lomé, BP 1515 Lomé, Togo
5. Department of Physics, Kunsan National University, Kunsan, 54150, Republic of Korea
6. Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 16419, Republic of Korea