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Using density functional theory and nonequilibrium Green's function method, we investigated the spin-dependent transport and spin-polarized optoelectronic properties of the 6,6,12-graphyne-based magnetic tunnel junction (MTJ) devices. The results show that the MTJ devices have prominent dual spin-filtering effect and large tunneling magnetoresistance (TMR); the TMR values of the MTJ devices are as high as 105%. In addition, we found that the spin-polarized photocurrents of the MTJ devices are dependent on the polarization direction of light and the magnetization directions of the electrodes. Two spin-polarized photocurrents can be realized in the MTJ devices and, if the magnetization directions of the two electrodes are antiparallel, the two light-generated spins flow in opposite directions. These interesting phenomena indicate that the 6,6,12-graphyne-based MTJ devices could be used as optoelectronic or opto-spintronic devices.

The promised performance of monolayer molybdenum disulfide (MoS2)-based devices is hindered by the high electrical resistance at the metal-MoS2 contact. Benefitting from the metallic phase of MoS2, 1T-MoS2 is considered a potential electrode material for the semiconducting 2H-MoS2. In this paper, we report a comparative study of the allotropic 1T/2H MoS2 contact with different contact types. The edge-contact interface has a low tunnel barrier, high charge density, and even Ohmic contact with no Schottky barrier, which implies that this contact may overcome the resistance limit for the electrode-MoS2 contact. The outstanding interface properties of the 1T/2H MoS2 edge contact originate from the excess in-plane dangling bonds in the edge position. Based on our results, the edge-contact model is ideal for the 1T/2H MoS2 contact and may solve the problem of MoS2 contact resistance.

The purpose of this paper is to present systematic procedure for synthesis of nonlinear controllers for complicate nonlinear systems. The approach utilizes an improved fuzzy basis function network (FBFN) to approximate the unknown nonlinear functions of unmolded dynamics, with adaptive laws to be applied to attenuate the effects of approximation errors and external disturbances. Based on the Lyapunov stability theory, the global stability analysis showed that the states and tracking errors of the system are uniformly bounded. Numerical results show that the new controllers achieve excellent tracking performance and exhibit insensitivity to parameter variations over a wide flight envelope.

In this state-of-the-art paper, important advances that have been made during the past years for BTT (Bank-to-turn) missile control algorithms are described. The paper reviews approaches in BTT missile autopilot with a focus on the problems raised in practical implementations by their nonlinear and uncertain properties. After a brief introduction on BTT missile, the paper explores the state-of-the-art in classical control theory, modern control theory, intelligent control theory and their combination for missile control issues, with short discussions and comments. The paper is concluded with remarks and future directions.

We investigated the upper critical fields of Ca10(Pt4As8)(Fe2–xPtxAs2)5 superconducting whiskers. The whiskers consist of several wire-like grains with diameter of around 200 nm, joined by grain boundaries whose misorientation angles are less than 5∘. The upper critical fields along c-axis and in ab-plane were observed as 49 T at 12 K and 50 T at 22 K, respectively, which can be extrapolated to ∼81 and ∼133 T at 0 K. The whisker demonstrated weak anisotropic factor and almost constant value of ∼2 below 15 K. The impressive transport properties of the whisker may find applications in fields like superconducting micro- and meso-structure systems.