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The electronic topology is generally related to the Berry curvature, which can induce the anomalous Hall effect in time-reversal symmetry breaking systems. Intrinsic monolayer transition metal dichalcogenides possesses two nonequivalent K and K′ valleys, having Berry curvatures with opposite signs, and thus vanishing anomalous Hall effect in this system. Here we report the experimental realization of asymmetrical distribution of Berry curvature in a single valley in monolayer WSe2 via applying uniaxial strain to break C3v symmetry. As a result, although the Berry curvature itself is still opposite in K and K′ valleys, the two valleys would contribute equally to nonzero Berry curvature dipole. Upon applying electric field E , the emergent Berry curvature dipole D would lead to an out-of-plane orbital magnetization M ∝ D ⋅ E , which further induces an anomalous Hall effect with a linear response to E2, known as nonlinear Hall effect. We show the strain modulated transport properties of nonlinear Hall effect in monolayer WSe2 with moderate hole-doping by gating. The second-harmonic Hall signals show quadratic dependence on electric field, and the corresponding orbital magnetization per current density M/J can reach as large as 60. In contrast to the conventional Rashba–Edelstein effect with in-plane spin polarization, such current-induced orbital magnetization is along the out-of-plane direction, thus promising for high-efficient electrical switching of perpendicular magnetization. [ABSTRACT FROM AUTHOR]

An n-TiO2/n-Si isotype heterojunction is fabricated by depositing TiO2 thin films onto n-Si substrates. Obvious photovoltaic behaviors are observed in this isotype heterojunction. The open circuit voltage and short circuit current of the heterojunction can reach 123mV and 20 μA/cm2, respectively. The mechanism for the photovoltaic behaviors can be understood in terms of the band alignment of the heterojunction. The results reported may provide a feasible route to easily available and low-cost isotyped photovoltaic devices. [ABSTRACT FROM AUTHOR]

The bias dependence of radiation-induced narrow-width channel effects (RINCEs) in 65-nm n-type metal-oxidesemiconductor field-effect transistors (NMOSFETs) is investigated. The threshold voltage of the narrow-width 65nm NMOSFET is negatively shifted by total ionizing dose irradiation, due to the RINCE. The experimental results show that the 65nm narrow-channel NMOSFET has a larger threshold shift when the gate terminal is kept in the ground, which is contrary to the conclusion obtained in the old generation devices. Depending on the three-dimensional simulation, we conclude that electric field distribution alteration caused by shallow trench isolation scaling is responsible for the anomalous RINCE bias dependence in 65nm technology. [ABSTRACT FROM AUTHOR]

During discharge, appropriately changing the development paths of electron avalanches and increasing the number of initial electrons can effectively inhibit the formation of filamentary discharge. Based on the aforementioned phenomenon, we propose a method of using microdischarge electrodes to produce a macroscopic discharge phenomenon. In the form of an asymmetric structure composed of a carbon fiber electrode, an electrode structure of carbon fiber spiral-contact type is designed to achieve an atmospheric pressure glow discharge in air, which is characterized by low discharge voltage, low energy consumption, good diffusion and less ozone generation. [ABSTRACT FROM AUTHOR]

The effects of proton irradiation on the subsequent time-dependent dielectric breakdown (TDDB) of partially depleted SOI devices are experimentally investigated. It is demonstrated that heavy-ion irradiation will induce the decrease of TDDB lifetime for many device types, but we are amazed to find a measurable increase in the TDDB lifetime and a slight decrease in the radiation-induced leakage current after proton irradiation at the nominal operating irradiation bias. We interpret these results and mechanisms in terms of the effects of radiation-induced traps on the stressing current during the reliability testing, which may be significant to expand the understanding of the radiation effects of the devices used in the proton radiation environment. [ABSTRACT FROM AUTHOR]

The effects of indium composition in InGaAs interlayer on morphology of GaSb/InGaAs quantum dots (QDs) and on optical properties of GaSb/InGaAs QD material system are studied. AFM images show that the change of the indium composition in InGaAs interlayer can alter the GaSb QD morphology. It is found that low indium composition in InGaAs interlayer can promote the formation of QDs, while high indium composition can inhibit the formation of QDs. The photoluminescence (PL) spectra of GaSb/InGaAs QDs at 8K under low excitation power indicate that the third root of the excitation power is linear with the peak position, which provides a direct evidence for their luminescence belonging to type-II material optical transition. The PL spectra at 8K under an excitation power of 90 mW show that the optical properties of GaSb/InGaAs QD material system can be affected by the indium composition in the InGaAs interlayer, and the PL peak position is linear with the indium composition. The optical properties of GaSb/InGaAs QDs can be improved by adjusting the indium composition in the InGaAs interlayer. [ABSTRACT FROM AUTHOR]

The influence of total dose irradiation on hot-carrier reliability of 65 nm n-type metal-oxide-semiconductor field-effect transistors (nMOSFETs) is investigated. Experimental results show that hot-carrier degradations on irradiated narrow channel nMOSFETs are greater than those without irradiation. The reason is attributed to radiation-induced charge trapping in shallow trench isolation (STI). The electric field in the pinch-off region of the nMOSFET is enhanced by radiation-induced charge trapping in STI, resulting in a more severe hot-carrier effect. [ABSTRACT FROM AUTHOR]