Nanowires of the wide band-gap semiconductor gallium nitride (GaN) have been shown to act as room-temperature uv lasers. Recent advances in nanomanipulation have made it possible to modify the shape of these structures from a linear to a pseudoring conformation. Changes to the optical boundary conditions of the lasing cavity affect the structure's photoluminescence, photon confinement, and lasi...

Terahertz radiation from InSb and InAS, which are typical narrow band-gap semiconductors, was investigated using time-resolved THz emission measurements. When we compared between the polarity of the THz waveforms of these narrow band-gap semiconductors with that of InP, which is a wide bandgap semiconductor, we concluded that the ultrafast buildup of the photo-Dember field is the main mechanism...

The synthesis of ZnO nanoparticles has attracted immense interest because of their unique properties and potential applications in optoelectronic devices. ZnO as a wide band gap semiconductor with large excitation energy becomes one of the most important functional material with near UV-emission, optical transparency, electric conductivity and piezoelectricity. ZnO nanoparticles were prepared b...

Wide band gap II-VI semiconductor nanostructures have been extensively studied according to their great potentials for optoelectronic applications, while heterojunctions are fundamental elements for modern electronic and optoelectronic devices. Subsequently, a great deal of achievements in construction and optoelectronic applications of heterojunctions based on II-VI compound semiconductor one-...

In general, anatase TiO2 exhibits higher photocatalytic activities than rutile TiO2. However, the reasons for the differences in photocatalytic activity between anatase and rutile are still being debated. In this work, the band structure, density of states, and effective mass of photogenerated charge carriers for anatase, rutile and brookite TiO2 are investigated by the first-principle density ...

Recently, an urgent requirement of ultraviolet (UV) semiconductor laser with lower cost and higher performance has motivated our intensive research in zinc oxide (ZnO) material owing to its wide direct band gap and large exciton binding energy. Here, we demonstrate for the first time continuous-wave laser in electrically-pumped hollow polygonal microcavities based on epitaxial ZnO/MgO-core/shel...

Dye-sensitized solar cells (DSSCs) have emerged as an innovative solar energy conversion technology which provides a pathway for the development of cheap, renewable and environmentally acceptable energy production (Gledhill, Scott et al., 2005; O'Regan & Grätzel, 1991; Shaheen, Ginley et al., 2005). A typical DSSC consists of a sensitizing dye chemically anchored to a nanocrystalline wide band ...

A three-terminal spectroscopy that probes both subsurface energy barriers and interband optical transitions in a semiconductor heterostructure is demonstrated. A metal-base transistor with a unipolar p-type semiconductor collector embedding InAs/GaAs quantum dots QDs is studied. Using minorityor majority-carrier injection, ballistic electron emission spectroscopy and its related hot-carrier sca...

New phenomena arise in single-crystal semiconductors when these are fabricated in very thin sheets, with thickness at the nanometer scale. We review recent research on Si and Ge nanomembranes, including the use of elastic strain sharing, layer release, and transfer, that demonstrate new science and enable the fabrication of materials with unique properties. Strain engineering produces new strai...

Network Materials In article number 2207492, Niklas Wolff, Ion Tiginyanu, Lorenz Kienle, and co-workers report on the synthesis structural characterization of a hybrid wide-band-gap semiconductor nanocomposite network interconnected hollow microtubes composed β-Ga2O3/ZnGa2O4 phases using X-ray powder diffraction transmission electron microscopy. The aero-network morphology shows ZnGa2O4-dominat...