Negative Capacitance in a Ferroelectric Capacitor

Asif Islam Khan; Korok Chatterjee; Brian Wang; Steven Drapcho; Long You; Claudy Serrao; Saidur Rahman Bakaul; Ramamoorthy Ramesh; Sayeef Salahuddin

arXiv · 1409.3273

Negative Capacitance in a Ferroelectric Capacitor

Asif Islam Khan·Korok Chatterjee·Brian Wang·Steven Drapcho·Long You·Claudy Serrao·Saidur Rahman Bakaul·Ramamoorthy Ramesh·Sayeef Salahuddin

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Abstract

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.

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Asif Islam Khan, Korok Chatterjee, Brian Wang, Steven Drapcho, Long You, Claudy Serrao, Saidur Rahman Bakaul, Ramamoorthy Ramesh, Sayeef Salahuddin. 2014-09-10. Negative Capacitance in a Ferroelectric Capacitor. https://arxiv.org/abs/1409.3273

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