Theory
In a short-circuited ferroelectric capacitor with a metal-ferroelectric-metal (MFM) structure, a charge distribution of screening charges forms at the metal-ferroelectric interface so as to screen the electric displacement of the ferroelectric. Due to these screening charges, there is a voltage drop across the ferroelectric capacitor with screening in the electrode layer that can be obtained using the Thomas-Fermi approach as follows :
Here is the film thickness, and are the electric fields in the film and electrode at the interface, is the spontaneous polarization, and & are the dielectric constants of the film and the metal electrode.
With perfect electrodes, or for thick films, with the equation reduces to:
Read more about this topic: Ferroelectric Capacitor
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