%0 Journal Article
%K Ferroelectric materials
%K Boltzmann equation
%K Ferroelectricity
%K Negative capacitance
%K Ferroelectric devices
%K Ferroelectric capacitors
%K Capacitance
%K Ferroelectric films
%K Energy dissipation
%K Capacitors
%K Boltzmann distribution
%K Direct measurement
%K Epitaxial ferroelectric films
%K Fundamental barriers
%K Intrinsic energy
%K New applications
%A A.I Khan
%A K Chatterjee
%A B Wang
%A S Drapcho
%A L You
%A C Serrao
%A S.R Bakaul
%A Ramamoorthy Ramesh
%A S Salahuddin
%B Nature Materials
%D 2015
%G eng
%I Nature Publishing Group
%P 182-186
%R 10.1038/nmat4148
%T Negative capacitance in a ferroelectric capacitor
%V 14
%X The Boltzmann distribution of electrons poses a fundamental barrier to lowering energy dissipation in conventional electronics, often termed as Boltzmann Tyranny. Negative capacitance in ferroelectric materials, which stems from the stored energy of a phase transition, could provide a solution, but a direct measurement of negative capacitance has so far been elusive. Here, we report the observation of negative capacitance in a thin, epitaxial ferroelectric film. When a voltage pulse is applied, the voltage across the ferroelectric capacitor is found to be decreasing with time - in exactly the opposite direction to which voltage for a regular capacitor should change. Analysis of this inductance -like behaviour from a capacitor presents an unprecedented insight into the intrinsic energy profile of the ferroelectric material and could pave the way for completely new applications. © 2015 Macmillan Publishers Limited. All rights reserved.