Crystalline Calcium Fluoride: A Record-Thin Insulator for Nanoscale 2D Electronics. - Yury Yu. Illarionov; Alexander G. Banshchikov; Theresia Knobloch; Dmitry K. Polyushkin; Stefan Wachter; V. V. Fedorov; S. M. Suturin; M. Stöger-Pollach; Thomas Mueller; M. I. Vexler; Nikolai S. Sokolov; Tibor Grasser (DRC, 2020)