Nitrogen Complex-Driven Vacancy Cluster in Group-III Nitrides.

A series of experiments have elucidated the primary defects in group-III nitride epilayers, identifying vacancy clusters due to cation migration at interfaces to mitigate strained lattice. While the occurrence of these defects is well-documented, the underlying electronic mechanisms driving vacancy agglomeration in nitrides and their alloys remain poorly understood. In this study, we uncovered a previously unreported ground state of two metal vacancies driven by the migration of kinetically unstable nitrogen atoms using an approach.

Highly efficient blue InGaN nanoscale light-emitting diodes.

Indium gallium nitride (InGaN)-based micro-LEDs (μLEDs) are suitable for meeting ever-increasing demands for high-performance displays owing to their high efficiency, brightness and stability. However, μLEDs have a large problem in that the external quantum efficiency (EQE) decreases with the size reduction. Here we demonstrate a blue InGaN/GaN multiple quantum well (MQW) nanorod-LED (nLED) with high EQE.

A molecular dynamics study on the interface morphology of vapor-deposited amorphous organic thin films.

The interfaces between amorphous organic layers play an important role in the efficiency and lifetime of organic light emitting diodes (OLEDs). However, an atomistic understanding of the interface morphology is still poor. In this study, we theoretically investigate the interfacial structure of amorphous organic films using molecular dynamics simulations that mimic vapor-deposition processes.

Role of preferential weak hybridization between the surface-state of a metal and the oxygen atom in the chemical adsorption mechanism.

We report on the chemical adsorption mechanism of atomic oxygen on the Pt(111) surface using angle-resolved-photoemission spectroscopy (ARPES) and density functional calculations. The detailed band structure of Pt(111) from ARPES reveals that most of the bands near the Fermi level are surface-states. By comparing band maps of Pt and O/Pt, we identify that dxz (dyz) and dz(2) orbitals are strongly correlated in the surface-states around the symmetry point M and K, respectively.

Anion control as a strategy to achieve high-mobility and high-stability oxide thin-film transistors.

Ultra-definition, large-area displays with three-dimensional visual effects represent megatrend in the current/future display industry. On the hardware level, such a "dream" display requires faster pixel switching and higher driving current, which in turn necessitate thin-film transistors (TFTs) with high mobility. Amorphous oxide semiconductors (AOS) such as In-Ga-Zn-O are poised to enable such TFTs, but the trade-off between device performance and stability under illumination critically limits their usability, which is related to the hampered electron-hole recombination caused by the oxygen vacancies.

Microscopic origin of universal quasilinear band structures of transparent conducting oxides.

A tight-binding-based microscopic theory is developed that accounts for quasilinear conduction bands appearing commonly in transparent conducting oxides. It is found that the interaction between oxygen p and metal s orbtials plays a critical role in determining the band structure around the conduction-band minimum. Under certain types of short-range orders, the tight-binding model universally leads to a dispersion relation which corresponds to that of the massive Dirac particle.

Chronic pure radiculopathy in patient with organizing epidural hematoma around C8 nerve root.

Spontaneously occurring spinal epidural hematomas are uncommon clinical findings, and the chronic form is the rarest and its most frequent location is the lumbar spine. Pure radicular involvement is far less frequent than myelopathy. We report a case of progressive radiculopathy in a 52-year-old man with spontaneously occurring cervical epidural hematoma (SCEH).

The clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody single level fusion.

Study Design: This is a retrospective study that was done according to clinical and radiological evaluation.

Purpose: We analyzed the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody single level fusion.

Overview Of Literature: Minimally invasive transforaminal lumbar interbody fusion is effective surgical method for treating degenerative lumbar disease.

Electrical manipulation of nanofilaments in transition-metal oxides for resistance-based memory.

The fabrication of controlled nanostructures such as quantum dots, nanotubes, nanowires, and nanopillars has progressed rapidly over the past 10 years. However, both bottom-up and top-down methods to integrate the nanostructures are met with several challenges. For practical applications with the high level of the integration, an approach that can fabricate the required structures locally is desirable.