In this paper, a numerical study of barrier characterization effects on the high-temperature internal performance of an InGaAsP multi-quantum well laser is presented. The softwareused for this purpose self-consistently combines the three-dimensional simulation of carrier transports, self-heating, and optical waveguiding. The laser model calculates all relevant physical mechanisms, including the...

III-nitride light-emitting diodes (LEDs) suffer from efficiency droop, which is partially attributed to electron leakage into the p-doped layers. Only very few direct measurements of such leakage are published. We here analyze leakage measurements on AlGaN LEDs with an emission wavelength near 260 nm. The electron leakage disappears after insertion of a thin undoped electron blocking layer (EBL...

This study provided baseline data required for a greater project, whose objective was to design a new Elekta electron collimation system having significantly lighter electron applicators with equally low out-of field leakage dose. Specifically, off-axis dose profiles for the electron collimation system of our uniquely configured Elekta Infinity accelerator with the MLCi2 treatment head were mea...

Nitride-based light-emitting diodes suffer from a reduction (droop) of the internal quantum efficiency (IQE) with increasing injection current. Using advanced device simulation, we investigate the impact of electron leakage on the IQE droop for different properties of the electron blocker layer (EBL). The simulations show a strong influence of the EBL acceptor density on the droop. We also find...

introduction: this study was carried out to evaluate the bacterial leakage of root canal fillings when cavity varnish containing 5% fluoride (duraflur) was used as root canal sealer. methods and materials: root canals of 88 straight single-rooted teeth were prepared. eighty teeth were randomly divided into 3 experimental groups ( n =20) and two positive and negative control groups of ten each. ...

Today, electron leakage in InP-based separate confinement laser diode has a serious effect on device performance. Control of electron leakage current is the aim of many studies in semiconductor laser industry. In this study, for the first time, a new asymmetric waveguide structure with n-interlayer for a 1.325 μm InP-based laser diode with InGaAsP multi-quantum well is proposed and theoreticall...

In this work, leakage radiation from EA200 series electron applicators on Siemens Primus accelerators is quantified, and its penetration ability in water and/or the shielding material Xenolite-NL established. Initially, measurement of leakage from 10 x 10 - 25 x 25 cm2 applicators was performed as a function of height along applicator and of lateral distance from applicator body. Relative to ce...

A model calculation for the field and hot carrier enhanced electron leakage in InGaAsP/InP LED’s and lasers is presented. The significant influence of the doping level in the P-InP confining layer on leakage current is confirmed. T HE temperature sensitivity and power saturation of InGaAsP lasers and light emitting diodes (LEDs) have triggered an extensive search for the responsible mechanisms....

Background: Intraoperative radiation therapy (IORT) technique is used to treat a surgically exposed tumor or tumor bed in the treatment of locally advanced intraabdominal, retroperitoneal, pelvic, thoracic, breast and soft tissue tumors. One way to perform IORT is to use an existing linac and modify the treatment head using an applicator system. In this study the objectives were to design, and ...