Structural inversion asymmetry controls the magnitude of Rashba spin-orbit coupling in the electron energy spectrum of a narrow band gap semiconductor. We investigate this effect for a series of two-dimensional electron gases in In0.52Ga0.48As quantum wells, surrounded by In0.52Al0.48As barriers, where either one or two electric subbands are populated. Structural inversion asymmetry does not ex...

Recent development advances have allowed silicon (Si) semiconductor technology to approach the theoretical limits of the Si material; however, power device requirements for many utility applications of power electronics are at a point that the present Si-based power devices cannot handle. The requirements include higher blocking voltages, switching frequencies, efficiency, and reliability. To o...

This study presents a novel visible light-active TiO₂ nanotube anode film by sensitization with Bi₂O₃ nanoparticles. The uniform incorporation of Bi₂O₃ contributes to largely enhancing the solar light absorption and photoelectric conversion efficiency of TiO₂ nanotubes. Due to the energy level difference between Bi₂O₃ and TiO₂, the built-in electric field is suggested to be formed in the Bi₂O₃ ...

The band structures of fully hydrogenated Si nanosheets and nanotubes are elucidated by the use of an empirical tight-binding model. The hydrogenated Si sheet is a semiconductor with an indirect band gap of about 2.2 eV. The symmetries of the wavefunctions allow us to explain the origin of the gap. We predict that, for certain chiralities, hydrogenated Si nanotubes represent a new type of semic...

We systematically studied the physical properties of a novel superhard (t-C₃N₄) and a novel hard (m-C₃N₄) C₃N₄ allotrope. Detailed theoretical studies of the structural properties, elastic properties, density of states, and mechanical properties of these two C₃N₄ phases were carried out using first-principles calculations. The calculated elastic constants and the hardness revealed that t-C₃N₄ i...

We simulated capacitance–voltage (C – V) curves of Si3N4 /GaAs, Si3N4 /Si and also Si3N4 /Semi* ~virtual semiconductor! metal–insulator–semiconductor ~MIS! capacitors and compared them with experimental C – V curves of a Si3N4 /Si/GaAs structure. The experimental C – V curves of the Si3N4 /Si/GaAs MIS capacitors are not in agreement with the simulated C – V curves of the Si3N4 /GaAs and Si3N4 /...

normal 0 false false false en-us x-none ar-sa microsoftinternetexplorer4 background : vitiligo as a common pigmentary disorder affects up to 2% of the general population. there are several treatment modalities in the literature but photo therapy is one of the best known with an improving effect. the goal of this study was to compare the efficacy of nb-uvb alone with adjunction of nb-uvb with ne...

An oxide semiconductor (perovskite-type Mn2 O3 ) is reported which has a narrow and direct bandgap of 0.45 eV and a high Vickers hardness of 15 GPa. All the known materials with similar electronic band structures (e.g., InSb, PbTe, PbSe, PbS, and InAs) play crucial roles in the semiconductor industry. The perovskite-type Mn2 O3 described is much stronger than the above semiconductors and may fi...