Direct measurement of internal quantum efficiency in light emitting diodes under electrical injection
Graph Chatbot
Chat with Graph Search
Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
Gallium Nitride (GaN) and its ternary alloys with aluminium and indium have met a growing interest in the last decade. These semiconductors have a large direct bandgap and can be doped with either silicon (Si) for n-type and magnesium (Mg) for p-type layer ...
In recent years, the fabrication of novel ultrathin film systems featuring multi-functionalities has been extensively studied due to their potential applications in photonics, sensors and solar cells. In a general sense, the primary goal of the present the ...
The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are rela ...
A quantum dot is a semiconductor nanostructure that confines the motion of conduction band electrons and valence band holes in all three spatial directions, thus creating fully discrete energy levels. The confinement in the InAs/GaAs material system is gen ...
A new, but archetypal compound [ Ir( ppy- F-2) (2)Me(4)phen] PF6, where ppy- F2 is 2-(2',4'- fluorophenyl) pyridine and Me(4)phen is 3,4,7,8- tetramethyl- 1,10- phenanthroline, was synthesized and used to prepare a solid-state light-emitting electrochemica ...
An experimental method is demonstrated for the determination of internal quantum efficiency (IQE) in III-nitride-based light-emitting diodes (LEDs). LED devices surrounded with an optically absorbing material have been fabricated to limit collected light t ...
The current density limit for photoemission from metals was measured in an rf photogun to be below 10(9) A/m(2). We have achieved 1.6 x 10(11) A/m(2) by photofield emission from a new type of photocathode made from a metallic-composite, multifilamentary Nb ...
High external quantum efficiency (EQE) p-i-n heterojunction solar cells grown by NH3-based molecular beam epitaxy are presented. EQE values including optical losses are greater than 50% with fill-factors over 72% when illuminated with a 1 sun AM0 spectrum. ...
A novel, highly blue luminescent molecule containing donor and acceptor groups, 4,4 prime -di-(2-(2,5-dimethoxyphenyl)ethenyl)-2,2 prime -bipyridine, that shows photoluminescence emission at 450 nm with 43% quantum yield is designed and synthesized. Time d ...
The light extraction efficiency of photonic-crystal (PhC) light-emitting diodes (LEDs) relies on the competition between the PhC extraction and dissipation mechanisms of the guided light within the LED. This work presents the experimental determination of ...
