1. Faculty of Physics and Engineering, Moldova State University, 60 Alexei Mateevici Str., MD-2009 Chisinau, Moldova
2. Functional Nanomaterials, Faculty of Engineering, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143 Kiel, Germany
3. Multicomponent Materials, Institute for Materials Science, Kiel University, Kaiserstr. 2, D-24143 Kiel, Germany
4. Center for Nanotechnology and Nanosensors, Department of Microelectronics and Biomedical Engineering, Technical University of Moldova, 168, Stefan cel Mare Av., MD-2004 Chisinau, Moldova
5. Department of Physics, University of Central Florida, Orlando, FL 32816-2385, USA
6. Faculty of Physics, Alexandru Ioan Cuza University of Iasi, 11 Carol I, 700506 Iasi, Romania
7. Science Research Department, Institute of Interdisciplinary Research, Research Center in Environmental Sciences for the North-Eastern Romanian Region (CERNESIM), Alexandru Ioan Cuza University of Iasi, 11 Carol I, 700506 Iasi, Romania