1. Rzhanov Institute of Semiconductor Physics SB RAS 13 Lavrentiev av. Novosibirsk 630090 Russia
2. Novosibirsk State Technical University 20 R Marx str. Novosibirsk 630073 Russia
3. Joint Institute for High Temperatures RAS 13 Bd.2 Izhorskaya str. Moscow 125412 Russia
4. Institute of Physics and Technologies Ammosov North-Eastern Federal University 58 Belinskii str. Yakutsk 67700 Russia
5. Novosibirsk State University 2 Pirogov str. Novosibirsk 630090 Russia