1. a D.V. Efremov Scientific Research Institute of Electrophysical Apparatus , Doroga na Metallostroy, 3 Metallostroy, St Petersburg, 19664, Russia
2. b A.F. Ioffe Physical-Technical Institute, Russian Academy of Sciences , 26 Polytekhnicheskaya Street, St Petersburg, 194021, Russia
3. c Nuclear Fusion Institute, Research Center, Kurchatov Institute , 1 Kurchatov Square, Moscow, 123182, Russia