1. Institute of Physics, J. Dlugosz Academy of Czestochowa, Al. Armii Krajowej 13/15, Czestochowa, Poland, Institute of Applied Physics, Military University of Technology, 2 Kaliskiego Str., 00-908 Warsaw, Poland, Faculty of Technical Physics, Poznan University of Technology, Nieszawska 13 A, 60-965 Poznan, Poland, Institute of Electronic Materials Technology, 133 Wolczanska Str., 01-919 Warsaw, Poland, and Laboratoire POMA, UMR CNRS 6136, Universite d'Angers, Angers, France