RESUMEN
Correction for 'Stabilization of negative capacitance in ferroelectric capacitors with and without a metal interlayer' by T. Rollo, et al., Nanoscale, 2020, 12, 6121-6129, DOI: 10.1039/C9NR09470A.
RESUMEN
The negative capacitance operation of a ferroelectric material is not only an intriguing materials science topic, but also a property with important technological applications in nanoscale electronic devices. Despite growing interest for possible applications, the very existence of negative capacitance is still actively debated, even because experimental results for ferroelectric capacitors with or without a metal interlayer led to quite contradicting indications. Here we present a comprehensive analysis of NC operation in ferroelectric capacitors and provide new insights into the discrepancies observed in experiments. Our models duly account for the three-dimensional nature of the problem and show a good agreement with several aspects of recent experiments. Our results also demonstrate that traps at the ferroelectric-dielectric interface play an important role in the feasibility of stable negative capacitance operation in ferroelectric capacitors.
RESUMEN
Monolayer graphene exhibits exceptional electronic and mechanical properties, making it a very promising material for nanoelectromechanical devices. Here, we conclusively demonstrate the piezoresistive effect in graphene in a nanoelectromechanical membrane configuration that provides direct electrical readout of pressure to strain transduction. This makes it highly relevant for an important class of nanoelectromechanical system (NEMS) transducers. This demonstration is consistent with our simulations and previously reported gauge factors and simulation values. The membrane in our experiment acts as a strain gauge independent of crystallographic orientation and allows for aggressive size scalability. When compared with conventional pressure sensors, the sensors have orders of magnitude higher sensitivity per unit area.