Optimization of Ternary InGaN Quantum Wells on GaN Microdisks for Full-Color GaN Micro-LEDs.

Red, green, and blue light InGaN multiple quantum wells have been grown on GaN/γ-LiAlO microdisk substrates by plasma-assisted molecular beam epitaxy. We established a mechanism to optimize the self-assembly growth with ball-stick model for InGaN multiple quantum well microdisks by bottom-up nanotechnology. We showed that three different red, green, and blue lighting micro-LEDs can be made of one single material (InGaN) solely by tuning the indium content.

Timing advances of commercial divalent-ion co-doped LYSO:Ce and SiPMs in sub-100 ps time-of-flight positron emission tomography.

Together with novel photodetector technologies and emerging electronic front-end designs, scintillator material research is one of the key aspects to obtain ultra-fast timing in time-of-flight positron emission tomography (TOF-PET). In the late 1990s, Cerium-doped lutetium-yttrium oxyorthosilicate (LYSO:Ce) has been established as the state-of-the-art PET scintillator due to its fast decay time, high light yield and high stopping power. It has been shown that co-doping with divalent ions, such as Caand Mg, is beneficial for its scintillation characteristics and timing performance.

Substrate-Induced Anisotropic Growth of CuAlO Platelets in a Liquid-Solid Reaction.

This study reports a simplified method to grow CuAlO crystals of submillimeter sizes with a highly anisotropic shape of a platelet. The solid-state reaction of forming CuAlO at ca. 1373 K in the first stage of the conventional flux method is no longer required.

A Review on Low-Dimensional Nanomaterials: Nanofabrication, Characterization and Applications.

The development of modern cutting-edge technology relies heavily on the huge success and advancement of nanotechnology, in which nanomaterials and nanostructures provide the indispensable material cornerstone. Owing to their nanoscale dimensions with possible quantum limit, nanomaterials and nanostructures possess a high surface-to-volume ratio, rich surface/interface effects, and distinct physical and chemical properties compared with their bulk counterparts, leading to the remarkably expanded horizons of their applications. Depending on their degree of spatial quantization, low-dimensional nanomaterials are generally categorized into nanoparticles (0D); nanorods, nanowires, and nanobelts (1D); and atomically thin layered materials (2D).

The Singularity Paramagnetic Peak of BiSbTe with p-type Surface State.

The magnetization measurement was performed in the BiSbTe single crystal. The magnetic susceptibility revealed a paramagnetic peak independent of the experimental temperature variation. It is speculated to be originated from the free-aligned spin texture at the Dirac point.

The Magnetic Susceptibility Bifurcation in the Ni-Doped SbTe Topological Insulator with Antiferromagnetic Order Accompanied by Weak Ferromagnetic Alignment.

The magnetic susceptibility reveals a discontinuity at Néel temperature and a hysteresis loop with low coercive field was observed below Néel temperature. The magnetic susceptibility of zero field cool and field cool processes coincide at a temperature above the discontinuity, and they split at temperature blow the discontinuity. The magnetic susceptibility splitting is larger at lower external magnetic fields.

Topological Proximity-Induced Dirac Fermion in Two-Dimensional Antimonene.

Antimonene is a promising two-dimensional (2D) material that is calculated to have a significant fundamental bandgap usable for advanced applications such as field-effect transistors, photoelectric devices, and the quantum-spin Hall (QSH) state. Herein, we demonstrate a phenomenon termed topological proximity effect, which occurs between a 2D material and a three-dimensional (3D) topological insulator (TI). We provide strong evidence derived from hydrogen etching on SbTe that large-area and well-ordered antimonene presents a 2D topological state.

Evaluation of the Feasibility of NaCaPO-Blended Zirconia as a New CAD/CAM Material for Dental Restoration.

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO-blended zirconia as a new CAD/CAM material.

Rational design of hetero-dimensional C-ZnO/MoS nanocomposite anchored on 3D mesoporous carbon framework towards synergistically enhanced stability and efficient visible-light-driven photocatalytic activity.

For efficient solar energy harvesting, various engineering strategies to strengthen visible-light responsivity of ZnO photocatalyst is under intensive investigation. In this work, a new ternary C-ZnO/MoS/mesoporous carbon nanocomposite was successfully prepared by a two-step solution-processed synthesis protocol. The ternary composite exhibits a well-interconnected 3D mesoporous microstructure assembled by carbon nanosheets, which is loaded with quasi 0D ZnO nanoparticles and 2D MoS nanosheets.

2D CTAB-MoSe Nanosheets and 0D MoSe Quantum Dots: Facile Top-Down Preparations and Their Peroxidase-Like Catalytic Activity for Colorimetric Detection of Hydrogen Peroxide.

We report the facile and economic preparation of two-dimensional (2D) and 0D MoSe nanostructures based on systematic and non-toxic top-down strategies. We demonstrate the intrinsic peroxidase-like activity of these MoSe nanostructures. The catalytic processes begin with facilitated decomposition of HO by using MoSe nanostructures as peroxidase mimetics.

Observation of Landau Level-Dependent Aharonov-Bohm-Like Oscillations in a Topological Insulator.

We study the quantum oscillations in the BiSbTe topological insulator. In addition to the Shubnikov-de Haas (SdH) oscillation, the Aharonov-Bohm-like (ABL) oscillations are also observed. The ABL oscillation period is constant at each Landau level (LL) which is determined from the SdH oscillation.

Facile Bottom-up Preparation of WS-Based Water-Soluble Quantum Dots as Luminescent Probes for Hydrogen Peroxide and Glucose.

Photoluminescent zero-dimensional (0D) quantum dots (QDs) derived from transition metal dichalcogenides, particularly molybdenum disulfide, are presently in the spotlight for their advantageous characteristics for optoelectronics, imaging, and sensors. Nevertheless, up to now, little work has been done to synthesize and explore photoluminescent 0D WS QDs, especially by a bottom-up strategy without using usual toxic organic solvents. In this work, we report a facile bottom-up strategy to synthesize high-quality water-soluble tungsten disulfide (WS) QDs through hydrothermal reaction by using sodium tungstate dihydrate and L-cysteine as W and S sources.

Enhancing thermoelectric performance by Fermi level tuning and thermal conductivity degradation in (GeBi)Te crystals.

In this work, a high thermoelectric figure of merit, zT of 1.9 at 740 K is achieved in GeBiTe crystals through the concurrent of Seebeck coefficient enhancement and thermal conductivity reduction with Bi dopants. The substitution of Bi for Ge not only compensates the superfluous hole carriers in pristine GeTe but also shifts the Fermi level (E) to an eligible region.

Fracture Resistance of Monolithic Zirconia Crowns in Implant Prostheses in Patients with Bruxism.

The aim of this study is to determine the minimum required thickness of a monolithic zirconia crown in the mandibular posterior area for patients with bruxism. Forty-nine full zirconia crowns, with seven different occlusal thicknesses of 0.4, 0.

The Extremely Enhanced Photocurrent Response in Topological Insulator Nanosheets with High Conductance.

The photocurrent was performed in topological insulator nanosheets with different conductances. The higher photocurrent is observed in the nanosheet with higher conductance. The responsivity is proportional to the nanosheet conductance over two orders.

In situ inward epitaxial growth of bulk macroporous single crystals.

The functionalities of porous materials could be significantly enhanced if the materials themselves were in single-crystal form, which, owing to structural coherence, would reduce electronic and optical scattering effects. However, growing macroporous single crystals remains a fundamental challenge, let alone manufacturing crystals large enough to be of practical use. Here we demonstrate a straightforward, inexpensive, versatile method for creating macroporous gallium nitride single crystals on a centimetre scale.

Growth and Characterization of -Plane GaN Thin Films Grown on -LiAlO (100) Substrates.

-plane GaN thin films were grown on LiAlO substrates under different N/Ga flux ratios by plasma-assisted molecular beam epitaxy. An anisotropic growth of -plane GaN was demonstrated against the N/Ga flux ratio. As the N/Ga flux ratio decreased by increasing Ga flux, the GaN surface trended to a flat morphology with stripes along [11[Formula: see text]0].

Ultrasensitive nonlinear absorption response of large-size topological insulator and application in low-threshold bulk pulsed lasers.

Dirac-like topological insulators have attracted strong interest in optoelectronic application because of their unusual and startling properties. Here we report for the first time that the pure topological insulator Bi2Te3 exhibited a naturally ultrasensitive nonlinear absorption response to photoexcitation. The Bi2Te3 sheets with lateral size up to a few micrometers showed extremely low saturation absorption intensities of only 1.

Fracture resistance of monolithic zirconia crowns with different occlusal thicknesses in implant prostheses.

Statement Of Problem: The use of monolithic zirconia crowns in implant prostheses is increasing, especially when the interdental space is insufficient. However, fractures have been reported in clinical practice.

Purpose: The purpose of this study was to determine the minimal thickness of a complete zirconia crown used for an implant prosthesis in the posterior dental region.

The synthesis route and the growth mechanism of aligned GaN nanobelts.

Crystallographically aligned GaN nanobelt arrays were synthesized through a hybrid process of Au-assisted nucleation followed by non-Au-assisted anisotropy vapor-solid growth on a (100) γ-LiAlO2 substrate. To the best of our knowledge, this is the first report on aligned GaN nanobelts.

Acoustic velocities of shear waves in La3Ga(5.5)Ta(0.5)O14 piezoelectric crystal using singular value decomposition.

La3Ga(5.5)Ta(0.5)O14 (LGT) is a new piezoelectric material with superior electromechanical properties and high Q.