Highly Monochromatic Ultraviolet LED Based on the SnO Microwire Heterojunction Beyond Dipole-Forbidden Band-Gap Transition.

SnO has been extensively applied in the fields of optoelectronic devices because of its large band gap, high exciton binding energy, and outstanding optical/electrical properties. However, its applications in ultraviolet light-emitting diodes (LEDs) are still hindered by the dipole-forbidden rule. Herein, the dipole-forbidden rule can be conquered by synthesizing Sb-incorporated SnO microwires (SnO:Sb MWs), which are examined by ultraviolet photoluminescence emitting at 363.

Electrically driven single microwire-based single-mode microlaser.

Engineering the lasing-mode oscillations effectively within a laser cavity is a relatively updated attentive study and perplexing issue in the field of laser physics and applications. Herein, we report a realization of electrically driven single-mode microlaser, which is composed of gallium incorporated zinc oxide microwire (ZnO:Ga MW) with platinum nanoparticles (PtNPs, d ~ 130 nm) covering, a magnesium oxide (MgO) nanofilm, a Pt nanofilm, and a p-type GaN substrate. The laser cavity modes could resonate following the whispering-gallery mode (WGM) among the six side surfaces by total internal reflection, and the single-mode lasing wavelength is centered at 390.

Numerical investigation of plasmon sensitivity and surface-enhanced Raman scattering enhancement of individual TiN nanosphere multimers.

Titanium nitride (TiN) nanoparticles have recently been considered as potential candidate plasmonic materials; such materials support localized surface plasmon resonances (LSPRs) and show excellent thermal stability with a high melting point. The electromagnetic (EM) field coupling and gap distance between components of individual TiN nanosphere multimers are critical parameters affecting their plasmonic sensitivity and surface-enhanced Raman scattering (SERS) performance, both of which are numerically investigated by the finite element method. It is demonstrated that the fractional shifts of both the dipolar LSPR wavelength [Formula: see text] and the refractive index sensitivity factor S follow the universal 'plasmon ruler' behavior, which is explained well in terms of EM field distribution.

Optimal geometry parameter for plasmonic sensitivities of individual Au nanopoarticle sensors.

The shape, aspect ratio and size are key parameters governing the plasmon sensitivities of individual Au nanoparticle bio/chemical sensors. It is crucial to unveil the general geometry parameters to optimize their corresponding sensitivity applications. In this work, the geometry-dependent refractive-index sensitivity factor (S) and figure of merit (FOM) of individual Au nanoparticle sensors (including a nanodisc, nanorod, nanoellipsoid and hexagonal nanoplate) are numerically investigated by discrete dipole approximation (DDA).

Articulation points in complex networks.

An articulation point in a network is a node whose removal disconnects the network. Those nodes play key roles in ensuring connectivity of many real-world networks, from infrastructure networks to protein interaction networks and terrorist communication networks. Despite their fundamental importance, a general framework of studying articulation points in complex networks is lacking.

The possibility of chemically inert, graphene-based all-carbon electronic devices with 0.8 eV gap.

Graphene is an interesting electronic material. However, flat monolayer graphene does not have significant gap in the electronic density of states, required for a large on-off ratio in logic applications. We propose here a novel device architecture, composed of self-folded carbon nanotube-graphene hybrids, which have been recently observed experimentally in Joule-heated graphene.

Universal scaling behavior of clustering coefficient induced by deactivation mechanism.

We propose a model of network growth that generalizes the deactivation model previously suggested for complex networks. Several topological features of this generalized model, such as the degree distribution and clustering coefficient, have been investigated analytically and by simulations. A scaling behavior of clustering coefficient C approximately 1/M is theoretically obtained, where M refers to the number of active nodes in the network.