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arXiv · 1709.10451

Differential voltage amplification from ferroelectric negative capacitance

Asif I. Khan·Michael Hoffmann·Korok Chatterjee·Zhongyuan Lu·Ruijuan Xu·Claudy Serrao·Samuel Smith·Lane W. Martin·Chenming C. Hu·Ramamoorthy Ramesh·Sayeef Salahuddin
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Abstract

It is well known that one needs an external source of energy to provide voltage amplification. Because of this, conventional circuit elements such as resistors, inductors or capacitors cannot provide amplification all by themselves. Here, we demonstrate that a ferroelectric can cause a differential amplification without needing such an external energy source. As the ferroelectric switches from one polarization state to the other, a transfer of energy takes place from the ferroelectric to the dielectric, determined by the ratio of their capacitances, which, in turn, leads to the differential amplification. {This amplification is very different in nature from conventional inductor-capacitor based circuits where an oscillatory amplification can be observed. The demonstration of differential voltage amplification from completely passive capacitor elements only, has fundamental ramifications for next generation electronics.

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Asif I. Khan, Michael Hoffmann, Korok Chatterjee, Zhongyuan Lu, Ruijuan Xu, Claudy Serrao, Samuel Smith, Lane W. Martin, Chenming C. Hu, Ramamoorthy Ramesh, Sayeef Salahuddin. 2017-09-29. Differential voltage amplification from ferroelectric negative capacitance. https://doi.org/10.1063/1.5006958

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