title: Electrostatic control of the evolution from a superconducting phase to an insulating phase in ultrathin YBa₂Cu₃O(7-x) films.
abstract: The electrical transport properties of ultrathin YBa₂Cu₃O(7-x) films have been modified using an electric double layer transistor configuration employing an ionic liquid. A clear evolution from superconductor to insulator was observed in nominally 7 unit-cell-thick films. Using a finite size scaling analysis, curves of resistance versus temperature, R(T), over the temperature range from 6 to 22 K were found to collapse onto a single scaling function, which suggests the presence of a quantum critical point. However, the scaling fails at the lowest temperatures indicating the possible presence of an additional phase between the superconducting and insulating regimes.
authors.affiliation: School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Xiang
authors.initials: X
authors.lastname: Leng
authors.forename: Javier
authors.initials: J
authors.lastname: Garcia-Barriocanal
authors.forename: Shameek
authors.initials: S
authors.lastname: Bose
authors.forename: Yeonbae
authors.initials: Y
authors.lastname: Lee
authors.forename: A M
authors.initials: AM
authors.lastname: Goldman