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A Weyl semimetal can be considered as a system composed of two Weyl cones breaking time-reversal symmetry, which exhibits strong anisotropic hyperbolic characteristics. The off diagonal components of the permittivity tensor of a Weyl semimetal produce the Faraday and Kerr effects. In this paper, we investigate the Goos–Hänchen (GH) shifts when a light is reflected from the interface of air and a Weyl semimetal. It is demonstrated that the angular GH shift is still tiny; however, the spatial GH shift can be huge and is very sensitive to change in the incident angle. The spatial GH shift can change from positive to negative with an increase in the incident angle. The spatial GH shifts vary at different distances of two Weyl cones and thicknesses of a Weyl semimetal film. Furthermore, the tunable GH shift can be realized by changing the tilting parameter and Fermi energy. These adjustable and giant GH shifts may find practical applications in optical shift devices and optical sensors.

Floating inductance simulators are designed in the paper. only two active components, one capacitor and one ground resistor are adopted in each simulator. A fifth-order low-pass filter is designed to verify the properties. All the circuits are simulated in a 0.18μm CMOS process. The consistent in the simulating results and the theoretical analysis results proves that the floating inductance simulators based on active components are reasonable and practicable.

In this paper, we theoretically reveal a 4 × 4 magneto-optical matrix to study the Kerr effects induced by the transverse-magnetic (TM) and transverse-electric (TE) polarized waves illuminating on a bulk Weyl semimetal (WSM). It is shown that the Kerr angles θp and θs maintain large absolute values of nearly 21°, which are mainly caused by the close cross-polarized and co-polarized reflection coefficients. What is more important, the Kerr angles can be further enhanced at two different frequencies close to the epsilon-near-zero (ENZ) frequency, where the maximum Kerr rotation angles (absolute value) of 45° have been obtained due to the sharp increases of the co-polarized reflection coefficients. Remarkably, the ENZ frequency of WSM can be adjusted by altering the Fermi energy and tilt degree, thereby resulting in the enhanced Kerr angles at different frequencies. Additionally, it is demonstrated that the incident angle should be declined with the increase of WSM thickness to enable the further enhancement of the Kerr angle θs. We also examine the effect of Weyl node separation on the Kerr angles. Our studies provide a simple and effective method to enhance and adjust the Kerr angles with a WSM or other topological semimetals.

The state-of-art Si Matel-Oxide-Semiconductor Field-Effect-Transistor (MOS-FET) meets the problem of the Power Consumption (P C ) can not be effecively deceased guided by the Moore’s Law as before. The GFET has the problem of the device can not be effectively turned off, since the band-gap of the graphene is zero. To solve these problems, noticing the amount of the carriers in the 2 dementional semiconductor material is limited, we propose a Matel-Semi-Insulator-Semiconductor Field-Effect-Transistor (MSIS-FET) to replace the traditional MOS-FET. We verify our idea by fabricating the graphene MSIS-FETs using the natural Aluminium-oxide (Al-oxide) as the semi-insulator gate dielectric. From MSIS-FETs fabricated, we obtain following experimental results. The graphene MSIS-FET is turned off very well, a recorded high Ids on/off ratio of 5 × 10 7 is achieved. A saddle and close-loop shape transfer feature of Ids-Vgs is obtained first time for transistors. A non-volatile memory characteristics is observed. A carrier re-injection principle and a super-Low P C mechanism for semiconductor devices and integrated circuits (ICs) are found from the transfer feature of the graphene MSIS-FET. It is shown that the P C of the semiconductor devices and (ICs) can be reduced by over three orders of magnitude by using this new mechanism.