1. Institute for Physical Research, Armenian National Academy of Sciences, Ashtarak-2, 0203, Armenia
2. Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR CNRS 5209, BP 47870, 21078 Dijon, France
3. Centre of Strong Field Physics, Yerevan State University, 1 A. Manukian St., Yerevan 0025, Armenia