1. Experimental Condensed Matter Physics Laboratory, Department of Physics, University of Cyprus, Nicosia 1678, Cyprus
2. Inorganic Nanocrystals Laboratory, Department of Chemistry, University of Cyprus, Nicosia 1678, Cyprus
3. Molecular Electronics and Photonics Research Unit, Department of Mechanical Engineering and Materials Science and Engineering, Cyprus University of Technology, Limassol 3603, Cyprus