Rh/InGaNO nanoarchitecture for light-driven methane reforming with carbon dioxide toward syngas.

Light-driven dry reforming of methane toward syngas presents a proper solution for alleviating climate change and for the sustainable supply of transportation fuels and chemicals. Herein, Rh/InGaNO nanowires supported by silicon wafer are explored as an ideal platform for loading Rh nanoparticles, thus assembling a new nanoarchitecture for this grand topic. In combination with the remarkable photo-thermal synergy, the O atoms in Rh/InGaNO can significantly lower the apparent activation energy of dry reforming of methane from 2.

Thermal modeling of electrically-pumped continuous-wave microring resonator-based topological insulator lasers.

Deleterious effects caused by Joule heating in electrically-pumped continuous-wave InP-based topological insulator lasers based on two-dimensional microring resonator arrays are estimated in this theoretical study. Steady-state temperature distributions within such an array are developed using a full numerical solution. Thermal interactions between active gain regions and ring resonators pose significant operational and integration challenges, as these devices are extremely sensitive to temperature-induced changes in a material's index of refraction.

A semiconducting hybrid of RhO/GaN@InGaN for simultaneous activation of methane and water toward syngas by photocatalysis.

Prior to the eventual arrival of carbon neutrality, solar-driven syngas production from methane steam reforming presents a promising approach to produce transportation fuels and chemicals. Simultaneous activation of the two reactants, i.e.

Enhancement in electro-optic performance of InAlGaAs/GaAs quantum dot lasers by ex situ thermal annealing.

This Letter reports the growth, fabrication, and characterization of molecular beam epitaxy (MBE)-grown quaternary InAlGaAs/GaAs quantum dot (QD) lasers emitting at sub-900 nm. The presence of Al in QD-based active regions acts as the origin of defects and non-radiative recombination centers. Applying optimized thermal annealing annihilates the defects in p-i-n diodes, thus lowering the reverse leakage current by six orders of magnitude compared to as-grown devices.

Length dependence thermal conductivity of zinc selenide (ZnSe) and zinc telluride (ZnTe) - a combined first principles and frequency domain thermoreflectance (FDTR) study.

In this study, we report the length dependence of thermal conductivity () of zinc blende-structured Zinc Selenide (ZnSe) and Zinc Telluride (ZnTe) for length scales between 10 nm and 10 μm using first-principles computations, based on density-functional theory. The value of ZnSe is computed to decrease significantly from 22.9 W m K to 1.

Sub-bandgap photoluminescence properties of multilayer h-BN-on-sapphire.

Two-dimensional hexagonal boron nitride (h-BN) materials have garnered increasing attention due to its ability of hosting intrinsic quantum point defects. This paper presents a photoluminescence (PL) mapping study related to sub-bandgap-level emission in bulk-like multilayer h-BN films. Spatial PL intensity distributions were carefully analyzed with 500 nm spatial resolution in terms of zero phonon line (ZPL) and phonon sideband (PSB) emission-peaks and their linewidths, thereby identifying the potential quantum point defects within the films.

Mid-infrared Lasers for Medical Applications: introduction to the feature issue.

This feature issue contains a series of papers that report the most recent advances in the field of mid-infrared light sources used for medical applications, including tissue imaging, reconstruction, excision, and ablation. Many biomolecular compounds have strong resonances in the mid-infrared region and medicine is ideally suited to exploit this. The precision, sterility, and versatility of light in mid-infrared is opening more opportunities and this feature issue captures some of the most exciting.

Intestinal iontophoresis from mucoadhesive patches: a strategy for oral delivery.

Biologics have limited permeability across the intestine and are prone to degradation in the acidic-proteolytic milieu of the gastrointestinal tract, leading to poor oral bioavailability. Iontophoresis is a promising technology that can substantially improve transport of drugs across biological barriers and has been particularly explored for skin. In this study, we investigated whether iontophoresis across the intestine can be utilized to improve oral insulin transport.

Near- to mid-IR (1-13 μm) III-V semiconductor lasers: introduction to the feature issue.

This feature issue reports on the most recent advances in the field of III-V semiconductor lasers emitting in the near- to mid-IR spectral regions, with a particular focus on devices with an emission wavelength range between 1 and 13 μm.

Heterodyne locking of a fully integrated optical phase-locked loop with on-chip modulators.

We design and experimentally demonstrate a highly integrated heterodyne optical phase-locked loop (OPLL) consisting of an InP-based coherent photonic receiver, high-speed feedback electronics, and an RF synthesizer. Such coherent photonic integrated circuits contain two widely tunable lasers, semiconductor optical amplifiers, phase modulators, and a pair of balanced photodetectors. Offset phase-locking of the two lasers is achieved by applying an RF signal to an on-chip optical phase modulator following one of the lasers and locking the other one to a resulting optical sideband.

Towards chip-scale optical frequency synthesis based on optical heterodyne phase-locked loop.

An integrated heterodyne optical phase-locked loop was designed and demonstrated with an indium phosphide based photonic integrated circuit and commercial off-the-shelf electronic components. As an input reference, a stable microresonator-based optical frequency comb with a 50-dB span of 25 nm (~3 THz) around 1550 nm, having a spacing of ~26 GHz, was used. A widely-tunable on-chip sampled-grating distributed-Bragg-reflector laser is offset locked across multiple comb lines.

Electric-field control of ferromagnetism in Mn-doped ZnO nanowires.

In this Letter, the electric-field control of ferromagnetism was demonstrated in a back-gated Mn-doped ZnO (Mn-ZnO) nanowire (NW) field-effect transistor (FET). The ZnO NWs were synthesized by a thermal evaporation method, and the Mn doping of 1 atom % was subsequently carried out in a MBE system using a gas-phase surface diffusion process. Detailed structural analysis confirmed the single crystallinity of Mn-ZnO NWs and excluded the presence of any precipitates or secondary phases.

Temperature dependence of electrical characteristics of Pt/GaN Schottky diode fabricated by UHV e-beam evaporation.

Temperature-dependent electrical characterization of Pt/n-GaN Schottky barrier diodes prepared by ultra high vacuum evaporation has been done. Analysis has been made to determine the origin of the anomalous temperature dependence of the Schottky barrier height, the ideality factor, and the Richardson constant calculated from the I-V-T characteristics. Variable-temperature Hall effect measurements have been carried out to understand charge transport at low temperature.