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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.

We demonstrate that a ferroelectric field-effect transistor (FeFET)-based spiking neuron is capable of mimicking various spiking and bursting patterns characteristic of cortical neurons. We propose a compact model to describe the dynamical behavior of such FeFET-based spiking neurons. This model captures the current-voltage dynamics of the FeFET and the critical voltages of its hysteretic region. It is aimed at system-level modeling and simulation of biomimetic networks of the FeFET neurons that are ideal for neuromorphic computing. [ABSTRACT FROM AUTHOR]

We demonstrate an electrically induced, non-volatile, metal-insulator phase transition in a MoS2 transistor. A ferroelectric capacitor made of single crystalline, epitaxially grown PbZr0.2Ti0.8O3 was connected to the gate of a field effect thin film MoS2 transistor. When a voltage is applied to this ferroelectric capacitor, a clear transition from an insulator to a metal and vice versa is observed in the transistor. Importantly, when the biased voltage is turned off, the remnant polarization in the ferroelectric can keep the MoS2 in its original phase, thereby providing a non-volatile state. Thus, a metallic or insulating phase can be written, erased, or retained simply by biasing the externally connected ferroelectric capacitor. [ABSTRACT FROM AUTHOR]

To further reduce the power dissipation in nanoscale transistors, the fundamental limit posed by the Boltzmann distribution of electrons has to be overcome. Stabilization of negative capacitance in a ferroelectric gate insulator can be used to achieve this by boosting the transistor gate voltage. Up to now, negative capacitance is only directly observed in polymer and perovskite ferroelectrics, which are incompatible with semiconductor manufacturing. Recently discovered HfO2-based ferroelectrics, on the other hand, are ideally suited for this application because of their high scalability and semiconductor process compatibility. Here, for the first time, a direct measurement of negative capacitance in polycrystalline HfO2-based thin films is reported. Decreasing voltage with increasing charge transients are observed in 18 and 27 nm thin Gd:HfO2 capacitors in series with an external resistor. Furthermore, a multigrain Landau-Khalatnikov model is developed to successfully simulate this transient behavior in polycrystalline ferroelectrics with nucleation limited switching dynamics. Structural requirements for negative capacitance in such materials are discussed. These results demonstrate that negative capacitance effects are not limited to epitaxial ferroelectrics, thus significantly extending the range of potential applications. [ABSTRACT FROM AUTHOR]

KCC activity in normal human red cells (containing haemoglobin A, HbA, and termed HbA cells) is O2-dependent, being active in oxygenated cells but inactive in deoxygenated ones. The mechanism for O2 dependence is unknown but a role for Hb has been suggested. In this paper, we address two main questions. First, do membrane ghosts prepared from HbA cells retain an O2-sensitive KCC activity? Second, how is the response of KCC to changes in O2 tension altered in sickle cell patients heterozygous for HbS and HbC? We found that substantial Cl−-dependent K+ influx, indicative of KCC activity, was present in both pink (5–10% normal Hb complement) and white (no measurable Hb) ghosts when equilibrated with air. KCC responded to deoxygenation in pink ghosts only (86±10% inhibition, mean±S.E.M., n=3), whilst KCC activity in white ghosts remained high (23±8% inhibition). Results indicate that pink ghosts retain an O2-dependent KCC activity but that this is lost in white ghosts. Second, HbSC-containing red cells showed sickling (88±3%) when deoxygenated, together with activation of the deoxygenation-induced cation pathway (Psickle) and the Gardos channel. KCC activity, however, was elevated in oxygenated HbSC cells, but inhibited by deoxygenation. Thus Hb polymerisation and sickling could be dissociated from the abnormal response of KCC to deoxygenation observed in HbS-containing red cells. These preparations provide a useful system with which to study the components involved in O2-sensitive membrane transport and why it is perturbed in certain pathological conditions (such as sickle cell disease and oxidant toxicity). [Copyright &y& Elsevier]

A correction is presented to the article "Differential voltage amplification from ferroelectric negative capacitance" which was published in the perodical.

To further reduce the power dissipation in nanoscale transistors, the fundamental limit posed by the Boltzmann distribution of electrons has to be overcome. Stabilization of negative capacitance in a ferroelectric gate insulator can be used to achieve this by boosting the transistor gate voltage. Up to now, negative capacitance is only directly observed in polymer and perovskite ferroelectrics, which are incompatible with semiconductor manufacturing. Recently discovered HfO2-based ferroelectrics, on the other hand, are ideally suited for this application because of their high scalability and semiconductor process compatibility. Here, for the first time, a direct measurement of negative capacitance in polycrystalline HfO2-based thin films is reported. Decreasing voltage with increasing charge transients are observed in 18 and 27 nm thin Gd:HfO2 capacitors in series with an external resistor. Furthermore, a multigrain Landau-Khalatnikov model is developed to successfully simulate this transient behavior in polycrystalline ferroelectrics with nucleation limited switching dynamics. Structural requirements for negative capacitance in such materials are discussed. These results demonstrate that negative capacitance effects are not limited to epitaxial ferroelectrics, thus significantly extending the range of potential applications. [ABSTRACT FROM AUTHOR]