This paper conducts a research on modulation characteristics of blue light-emitting diodes (LEDs) used in a visible-light communication (VLC) system. Through analysis of the modulation characteristics of LEDs with different emitting sizes, we find that there is a similar linear relationship between LED’s 3dB bandwidth and the operation current density. This experiment also shows that high serie...

Due to the wide band gap energy and high breakdown electric field of GaN, heterostructure transistors made from it are promising candidates for high power and high frequency applications. However, one issue that prevents the wide deployment of GaN HEMTs is their reliability. Research has been actively trying to improve the reliability of these devices. In spite of this, detailed understanding o...

Microwave GaN technology is now in production and poised to revolutionize many of today’s radar and communication systems. Simultaneously, mm-wave GaN processes are rapidly being matured to meet the growing needs of high power and efficiency, at higher frequencies. In this paper, we present an overview of GaN development, focusing on reliability and affordability for defense applications.

Guillain-Barré syndrome is an autoimmune disorder o€en considered a postinfectious polyneuropathy involving mainly motor but also sensory and sometimes autonomic nerves. is syndrome a‚ects people of all ages and is not hereditary. Most patients in the United States and Europe have a demyelinating neuropathy, but primarily axonal degeneration is documented in some cases, mainly in China, Mexico...

In uraemic and other patients with neuropathies, motor unit spike intervals were analysed using a special computer program to detect prolonged intervals of twice the normal duration, so-called "double intervals." These may have different causes--trigger failure, double discharge, or a transient fall in the firing rate of coactive motor units. There was not sufficient evidence that transient con...

Multi-color and broadband visible emission was realized thorough the hexagonal annular structure of GaN. The annular structure fabricated by selective-area growth emitted purple, blue and green color-emission from the multi-facets. The hexagonal annular structure provided various sidewalls of {101} and {112} semi-polar facets, and (0001) polar facet. From the cathodoluminescence study, the (000...

In this article two methods for improvements of (112̄2) oriented semipolar GaN grown by MOVPE on pre-structured sapphire substrates are investigated. The integration of a SiNx interlayer helps to obtain a better crystal quality. Also the overgrowth of the MOVPE samples by HVPE is a way to obtain a smoother GaN surface. A high incorporation of oxygen on (112̄2) oriented GaN compared to (0001) orie...

We report on a comparative study of the low temperature emission and polarisation properties of InGaN/GaN quantum wells grown on nonpolar ([Formula: see text]) a-plane and ([Formula: see text]) m-plane free-standing bulk GaN substrates where the In content varied from 0.14 to 0.28 in the m-plane series and 0.08 to 0.21 for the a-plane series. The low temperature photoluminescence spectra from b...