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

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.