Map to Majorana fermions in nanowires is revealed.

No abstract

We perform tunneling measurements on indium antimonide nanowire/superconductor hybrid devices fabricated for the studies of Majorana bound states. At finite magnetic field, resonances that strongly resemble Majorana bound states, including zero-bias pinning, become common to the point of ubiquity. Since Majorana bound states are predicted in only a limited parameter range in nanowire devices, we seek an alternative explanation for the observed zero-bias peaks. With the help of a self-consistent Poission-Schrödinger multiband model developed in parallel, we identify several families of trivial subgap states which overlap and interact, giving rise to a crowded spectrum near zero energy and zero-bias conductance peaks in experiments. These findings advance the search for Majorana bound states through improved understanding of broader phenomena found in superconductor-semiconductor systems.

A mesoscale, variational simulation of grain growth in two-dimensions has been used to explore the effects of grain boundary properties on the grain boundary character distribution. Anisotropy in the grain boundary energy has a stronger influence on the grain boundary character distribution than anisotropy in the grain boundary mobility. As grain growth proceeds from an initially random distribution, the grain boundary character distribution reaches a steady state that depends on the grain boundary energy. If the energy depends only on the lattice misorientation, then the population and energy are related by the Boltzmann distribution. When the energy depends on both lattice misorientation and boundary orientation, the steady state grain boundary character distribution is more complex and depends on both the energy and changes in the gradient of the energy with respect to orientation.

No abstract

No abstract

Solar-blind deep-ultraviolet photodetectors are one of the most effective tools to detect corona discharge because high-voltage corona discharge is always accompanied by deep-ultraviolet light (UVC, 200-280 nm), referred to as solar-blind signals. In this study, a fully transparent metal-semiconductor-metal (MSM) solar-blind photodetector with AZO (Al-doped ZnO) transparent electrodes was successfully constructed based on amorphous Ga2O3 film (a-Ga2O3) and prepared by radio frequency magnetron sputtering. The as-fabricated fully transparent device exhibits excellent performance, including an ultra-low dark current of 2.84 pA, a high photo-to-dark current ratio of 1.41×107, superb rejection ratio (R254/R400 = 2.93×105), a large responsivity of 2.66 A/W, superb detectivity (4.84×1014 Jones), and fast response speed (rise/fall time: 24 μs/1.24 ms). It is worth noting that the fully transparenta-Ga2O3 photodetector demonstrates ultra-high sensitivity to weak solar-blind signals, far below the 100 nW/cm2 threshold of the test equipment. It also has high-resolution detection capabilities for subtle changes in radiation intensity. Acting as a sensor for the high-voltage corona discharge simulation detection system, the fully transparent a-Ga2O3 photodetector can clearly detect extremely weak solar-blind signals. The results described in this work serve as proof-of-concept for future applications of amorphous Ga2O3 solar-blind deep-ultraviolet photodetectors in high-voltage corona discharge detection.

The critical current response to an applied out-of-plane magnetic field in a Josephson junction provides insight into the uniformity of its current distribution. In Josephson junctions with semiconducting weak links, the carrier density, and therefore the overall current distribution, can be modified electrostatically via metallic gates. Here, we show local control of the current distribution in an epitaxial Al-InAs Josephson junction equipped with five minigates. We demonstrate that not only can the junction width be electrostatically defined but also the current profile can be locally adjusted to form superconducting quantum interference devices. Our studies show enhanced edge conduction in such long junctions, which can be eliminated by minigates to create a uniform current distribution.