Charge transport performance of high resistivity CdZnTe crystals doped with In/Al

To evaluate the charge transport properties of as-grown high resistivity CdZnTe crystals doped with In/Al, the α particle spectroscopic response was measured using an un-collimated 241Am （5.48 MeV） radioactive source at room temperature. The electron mobility lifetime products （μτ）e of the CdZnTe crystals were predicted by fitting plots of photo-peak position versus electrical field strength using the single carrier Hecht equation. A TOF technique was employed to evaluate the electron mobility for CdZnTe crystals. The mobility was obtained by fitting the electron drift velocities as a function of the electrical field strengths, where the drift velocities were achieved by analyzing the rise-time distributions of the voltage pulses formed by a preamplifier. A fabricated CdZnTe planar detector based on a low In concentration doped CdZnTe crystal with （μτ）e = 2.3 × 10？3 cm2/V and μe =1000 cm2/（V·s）, respectively, exhibits an excellent γ-ray spectral resolution of 6.4% （FWHM = 3.8 keV） for an un-collimated 241Am @ 59.54 keV isotope.

Engineering two-dimensional pores in freestanding TiO_2/graphene gel film for high performance lithium ion battery

As the key component of electrochemical energy storage devices, an electrode with superior ions transport pores is the important premise for high electrochemical performance. In this paper, we developed a unique solution process to prepare freestanding TiO_2/graphene hydrogel electrode with tunable density and porous structures. By incorporating room temperature ionic liquids（RTILs）, even upon drying, the non-volatile RTILs that remained in the gel film would preserve the efficient ion transport channels and prevent the electrode from closely stacking, to develop dense yet porous structures. As a result, the dense TiO_2/graphene gel film as an electrode for lithium ion battery displayed a good gravimetric electrochemical performance and more importantly a high volumetric performance.

The visual analytics of big,open public transport data-a framework and pipeline for monitoring system performance in Greater Sydney

Many cities,countries and transport operators around the world are striving to design intelligent transport systems.These systems capture the value of multisource and multiform data related to the functionality and use of transportation infrastructure to better support human mobility,interests,economic activity and lifestyles.They aim to provide services that can enable transportation customers and managers to be better informed and make safer and more efficient use of infrastructure.In developing principles,guidelines,methods and tools to enable synergistic work between humans and computer-generated information,the science of visual analytics continues to expand our understanding of data through effective and interactive visual interfaces.In this paper,we describe an application of visual analytics related to the study of movement and transportation systems.This application documents the use of rapid,2D and 3D web visualisation and data analytics libraries and explores their potential added value to the analysis of big public transport performance data.A novel approach to displaying such data through a generalisable framework visualisation system is demonstrated.This framework recalls over a year’sworth of public transport performance data at a highly granular level in a fast,interactive browser-based environment.Greater Sydney,Australia forms a case study to highlight potential uses of the visualisation of such large,passively-collected data sets as an applied research scenario.In this paper,we argue that such highly visual systems can add data-driven rigour to service planning and longer-term transport decision-making.Furthermore,they enable the sharing of quality of service statistics with various stakeholders and citizens and can showcase improvements in services before and after policy decisions.The paper concludes by making recommendations on the value of this approach in embedding these or similar web-based systems in transport planning practice,performance management,optimisation and understanding of customer experience.

Economics and Performance of 10 Gb/s Metro Transport Over Mixed Fiber Plant of G.655 NZDF and G.652.C Zero Water-Peak Fibers

Using lower-cost lasers, 30% savings are possible for 10-Gb/s uncompensated metro transmission over NZDF, compared to G.652 fiber. We present WDM transmission results for a mixed plant of NZDF rings interconnected to G.652.C-fiber access laterals.

High-performance sub-10-nm monolayer black phosphorene tunneling transistors

Moore＇s law is approaching its physical limit. Tunneling field-effect transistors （TFETs） based on two-dimensional （2D） materials provide a possible scheme to extend Moore＇s law down to the sub-10-nm region owing to the electrostatic integrity and absence of dangling bonds in 2D materials. We report an ab initio quantum transport study on the device performance of monolayer （ML） black phosphorene （BP） TFETs in the sub-10-nm scale （6-10 nm）. Under the optimal schemes, the ML BP TFETs show excellent device performance along the armchair transport direction. The on-state current, delay time, and power dissipation of the optimal sub-10-nm ML BP TFETs significantly surpass the latest International Technology Roadmap for Semiconductors （ITRS） requirements for high- performance devices. The subthreshold swings are 56-100 mV/dec, which are much lower than those of their Schottky barrier and metal oxide semiconductor field-effect transistor counterparts.

Enhanced carrier mobility in MoSe_(2) by pressure modulation

Two-dimensional(2D)materials hold great potential for the development of next-generation integrated circuits(ICs)at the atomic limit.However,it is still very challenging to build high performance devices.One of the main factors that limit the incorporation of 2D materials into IC technology is their relatively low carrier mobility.Thus,the engineering strategies that focus on optimizing performance continue to emerge.Herein,using a spatiotemporal resolved pump-probe setup,the carrier transport performance and relaxation process of few-layer and bulk MoSe_(2) under pressure were investigated nondestructively and simultaneously.Our results show that pressure can tune the transport performance effectively.In particular,under pressure regulation,the carrier mobility of the bulk MoSe_(2) increases by~4 times;meanwhile,the carrier lifetimes of the samples become shorter.Although the processes almost return to their initial state after the pressure release,it is still surprising to see that the carrier mobilities of fewlayer and bulk MoSe2 are still~1.5 and 2 times enhanced,and carrier lifetimes are still shorter than the initial state.Combined with the Raman spectra under pressure,we consider that it is caused by the enhanced layer coupling and lattice compression.The combination of enhanced mobility and shortened lifetime in MoSe_(2) under pressure holds great potential for optoelectronic applications under the deep ocean and deep earth.

MoS2/MnO2 heterostructured nanodevices for electro- chemical energy storage

Hybrid or composite heterostructured electrode materials have been widely studied for their potential application in electrochemical energy storage. Whereas their physical or chemical properties could be affected significantly by modulating the heterogeneous interface, the underlying mechanisms are not yet fully understood. In this work, we fabricated an electrochemical energy storage device with a MoS2 nanosheet/MnO2 nanowire heterostructure and designed two charge/discharge channels to study the effect of the heterogeneous interface on the energy storage performances. Electrochemical measurements show that a capadty improvement of over 50% is achieved when the metal current collector was in contact with the MnO2 instead of the MoS2 side. We propose that this enhancement is due to the unidirectional conductivity of the MoS2/MnO2 heterogeneous interface, resulting from the unimpeded electrical transport in the MnO2-MoS2 channel along with the blocking effect on the electron transport in the MoS2-MnO2 channel, which leads to reaction kinetics optimization. The present study thus provides important insights that will improve our understanding of heterostructured electrode materials for electrochemical energy storage.