A new form of spontaneously polarized material

Abstract

We report here the discovery of a new form of spontaneously polarized material. Examples of this material, in the form of films, demonstrate the property that they spontaneously harbour electric fields which may exceed 10⁸Vm⁻¹, achieving potentials of tens of volts on the film surface. The molecules presently identified form a diverse group, thus far of six species, with gas phase dipoles lying between 0.08 D and 0.5 D: propane (0.08 D), isopentane (0.13 D), nitrous oxide (0.167 D), isoprene (0.25 D), toluene (0.385 D) and CF₃Cl (Freon-13; 0.5 D). Here we concentrate on an understanding of the nature of the interactions which give rise to the spontaneously polarized state, using the measured temperature dependence of the electric field in N₂O as a diagnostic. We show that the polarized state can arise through a mechanism of non-linear dipole alignment in a single domain in which dipole alignment generates the electric field within the film and the field generates dipole alignment. Non-local interactions take place over the dimension of the thickness of the film and permeate the entire medium through the agency of the electric field. This new type of material may have wide ranging applications in devices and in nanotechnology.