Integration of ferroelectric materials into nanoscale field-effect transistors offers enormous promise for superior transistor performance and also intriguing memory effects. In this study, we have incorporated lead zirconate titanate (PZT) into In2O3 nanowire transistors to replace the commonly used SiO2 as the gate dielectric. These transistors exhibited substantially enhanced performance as a result of the high dielectric constant of PZT, as revealed by a 30-fold increase in the transconductance and a 10-fold reduction in the subthreshold swing when compared to similar SiO2-gated devices. Furthermore, memory effects were observed with our devices, as characterized by a counter-clockwise loop in current-versus-gate-bias curves that can be attributed to the switchable remnant polarization of PZT. Our method can be easily generalized to other nanomaterials systems and may prove to be a viable way to obtain nanoscale memories.

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aMotivated by the recent realization of two-dimensional (2D) nanomaterials as gas sensors, we have investigated the adsorption of gas molecules (SO 2 , NO 2 , HCN, NH 3 , H 2 S, CO, NO, O 2 , H 2 , CO 2 , and H 2 O) on the graphitic GaN sheet (PL-GaN) using density functional theory calculations. It is found that among these gases, only SO 2 and NH 3 gas molecules are chemisorbed on the PL-GaN sheet with apparent charge transfer and reasonable adsorption energies. The electronic properties (especially the electric conductivity) of the PL-GaN sheet showed dramatic changes after the adsorption of NH 3 and SO 2 molecules. However, the strong adsorption of SO 2 on the PL-GaN sheet makes desorption difficult, which precludes its application to SO 2 sensors. Therefore, the PL-GaN sheet should be a highly sensitive and selective NH 3 sensor with short recovery time. Furthermore, the adsorption of NO (or NO 2 ) molecules introduces spin polarization in the PL-GaN sheet with a magnetic moment of about 1 m B , indicating that magnetic properties of the PL-GaN sheet are changed obviously. Based on the change of magnetic properties of the PL-GaN sheet before and after molecule adsorption, the PL-GaN sheet could be used as a highly selective magnetic gas sensor for NO and NO 2 detection.

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Until recently, work on executive function (EF) and on emotionrelated self-regulation proceeded on separate tracks with relatively little overlap. EF, especially that of children, was the domain of neuroscientists, clinicians, and educational psychologists interested in academic or cognitive functioning (e.g.,