Negative Capacitance in a Ferroelectric Capacitor
  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 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 behavior 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. 
Asif Islam Khan, Korok Chatterjee, Brian Wang, Steven Drapcho, Long   You, Claudy Serrao, Saidur Rahman Bakaul, Ramamoorthy ...
cond-mat.mes-hall cond-mat.mtrl-sci cond-mat.str-el