1. Physics Department, Faculty of Electrical Engineering, Czech Technical University in Prague, 16227 Prague, Czech Republic
2. Biological Physics and Medical Informatics Department, Bukovinian State Medical University, 58000 Chernivtsi, Ukraine
3. Electronics and Energy Department, Applied-Physics and Computer Sciences Institute, Yuriy Fedkovich Chernivtsi National University, 58012 Chernivtsi, Ukraine