title: Gate-tunable electron interaction in high-κ dielectric films.
abstract: The two-dimensional (2D) logarithmic character of Coulomb interaction between charges and the resulting logarithmic confinement is a remarkable inherent property of high dielectric constant (high-κ) thin films with far reaching implications. Most and foremost, this is the charge Berezinskii-Kosterlitz-Thouless transition with the notable manifestation, low-temperature superinsulating topological phase. Here we show that the range of the confinement can be tuned by the external gate electrode and unravel a variety of electrostatic interactions in high-k films. We find that by reducing the distance from the gate to the film, we decrease the spatial range of the 2D long-range logarithmic interaction, changing it to predominantly dipolar or even to exponential one at lateral distances exceeding the dimension of the film-gate separation. Our findings offer a unique laboratory for the in-depth study of topological phase transitions and related phenomena that range from criticality of quantum metal- and superconductor-insulator transitions to the effects of charge-trapping and Coulomb scalability in memory nanodevices.
authors.affiliation: University of Picardie, Laboratory of Condensed Matter Physics, Amiens, 80000, France.
authors.forename: Svitlana
authors.initials: S
authors.lastname: Kondovych
authors.affiliation: University of Picardie, Laboratory of Condensed Matter Physics, Amiens, 80000, France.|ITMO University, 49 Kronverksky Pr., St. Petersburg, 197101, Russia.
authors.forename: Igor
authors.initials: I
authors.lastname: Luk'yanchuk
authors.affiliation: University of Regensburg, Universitätsstraße 31, Regensburg 93053, Germany.|A. V. Rzhanov Institute of Semiconductor Physics SB RAS, 13 Lavrentjev Avenue, Novosibirsk 630090, Russia.|Novosibirsk State University, Pirogova str. 2, Novosibirsk 630090, Russia.
authors.forename: Tatyana I
authors.initials: TI
authors.lastname: Baturina
authors.affiliation: Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Lemont, Illinois 60439, USA.|Computation Institute, University of Chicago, 5735 S. Ellis Avenue, Chicago, IL 60637, USA.
authors.forename: Valerii M
authors.initials: VM
authors.lastname: Vinokur