Changes in Metallicity and Electronic Structure Across the Surface Ferroelectric Transition of Ultrathin Crystalline Poly(vinylidene Fluoride-Trifluoroethylene) Copolymers

Authors

• Jaewu Choi, University of Nebraska-LincolnFollow
• Peter A. Dowben, University of Nebraska-LincolnFollow
• Shawn Pebley, University of Nebraska-Lincoln
• A.V. Bune, University of Nebraska-Lincoln
• Stephen Ducharme, University of NebraskaFollow
• V.M. Fridkin, Institute of Crystallography, The Russian Academy of Sciences, Moscow, Russia
• S.P. Palto, Institute of Crystallography, The Russian Academy of Sciences, Moscow, Russia
• N. Petukhova, Institute of Crystallography, The Russian Academy of Sciences, Moscow, Russia

Document Type

Article

Date of this Version

2-9-1998

Comments

Published American Physical Society. Copyright 1998. Permission to use. Phys. Rev. Lett. 80 (1998) 1328-1331. http://prb.aps.org/.

Abstract

The surface ferroelectric-paraelectric phase transition in crystalline copolymer films of vinylidene fluoride (70%) with trifluoroethylene (30%), at about 20 °C, is accompanied by a dramatic change in both the electronic structure and metallicity. The temperature-dependent changes in the electronic structure occur primarily in the conduction band. This P(VDF-TrFE 70:30) material is observed to resemble an n-type semiconductor, and the change in electronic structure at the surface ferroelectric transition resembles a semiconductor-to-semimetal transition.