Does P-type Ohmic Contact Exist in WSe2-metal Interfaces?

Formation of low-resistance metal contacts is the biggest challenge that masks the intrinsic exceptional electronic properties of 2D WSe2 devices. We present the first comparative study of the interfacial properties between ML/BL WSe2 and Sc, Al, Ag, Au, Pd, and Pt contacts by using ab initio energy band calculations with inclusion of the spin-orbital coupling (SOC) effects and quantum transport simulations. The interlayer coupling tends to reduce both the electron and hole Schottky barrier heights (SBHs) and alters the polarity for WSe2-Au contact, while the SOC chiefly reduces the hole SBH. In the absence of the SOC, Pd contact has the smallest hole SBH with a value no less than 0.22 eV. Dramatically, Pt contact surpasses Pd contact and becomes p-type Ohmic or quasi-Ohmic contact with inclusion of the SOC. Our study provides a theoretical foundation for the selection of favorable metal electrodes in ML/BL WSe2 devices

Below the 12-vertex: 10-vertex carborane anions as non-corrosive, halide free, electrolytes for rechargeable Mg batteries

The development of practical Mg based batteries is limited by the lack of a library of suitable electrolytes. Recently a 12-vertex closo-carborane anion based electrolyte has been shown to be the first electrolyte for Mg based batteries, which is both non-corrosive and has high electrochemical stability (+3.5 V vs. Mg0/2+). Herein we show that smaller 10-vertex closo-carborane anions also enable electrolytes for Mg batteries. Reduction of the trimethylammonium cation of [HNMe31+][HCB9H91-] with elemental Mg yields the novel magnesium electrolyte [Mg2+][HCB9H91-]2. The electrolyte displays excellent electrochemical stability, is non-nucleophilic, reversibly deposits and strips Mg, and is halide free. This discovery paves the way for the development of libraries of Mg electrolytes based on more cost effective 10-vertex closo-carborane anions

Railway track switch model, including an actuator and switch blades

This railway track switch model includes an electromechanical actuator model and a switch blade model using Finite element analysis built in Matlab/ Simulink. It supplements the Paper: ‘Railway track switch simulation: A new dynamic model for studying actuator and switch blade dynamics’

Research and Analysis of MEMS Switches in Different Frequency Bands

Due to their high isolation, low insertion loss, high linearity, and low power consumption, microelectromechanical systems (MEMS) switches have drawn much attention from researchers in recent years. In this paper, we introduce the research status of MEMS switches in different bands and several reliability issues, such as dielectric charging, contact failure, and temperature instability. In this paper, some of the following methods to improve the performance of MEMS switches in high frequency are summarized: (1) utilizing combinations of several switches in series; (2) covering a float metal layer on the dielectric layer; (3) using dielectric layer materials with high dielectric constants and conductor materials with low resistance; (4) developing MEMS switches using T-match and π-match; (5) designing MEMS switches based on bipolar complementary metal–oxide–semiconductor (BiCMOS) technology and reconfigurable MEMS’ surfaces; (6) employing thermal compensation structures, circularly symmetric structures, thermal buckle-beam actuators, molybdenum membrane, and thin-film packaging; (7) selecting Ultra-NanoCrystalline diamond or aluminum nitride dielectric materials and applying a bipolar driving voltage, stoppers, and a double-dielectric-layer structure; and (8) adopting gold alloying with carbon nanotubes (CNTs), hermetic and reliable packaging, and mN-level contact