1. Laboratory of Terahertz Spectroscopy, Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Moscow Region, Russia
2. Sobolev Institute of Geology and Mineralogy, RAS, 630090 Novosibirsk, Russia
3. Novosibirsk State University, 630090 Novosibirsk, Russia