Now showing items 21-30 of 45
Near resonant and nonresonant third-order optical nonlinearities of colloidal InP/ZnS quantum dots
We have investigated the third-order optical nonlinearities of high-quality colloidal InP/ZnS core-shell quantum dots (QDs) using Z-scan technique with femtosecond pulses. The two-photon absorption cross-sections as high ...
High-quality InP/ZnS nanocrystals with high photometric performance and their application to white quantum dot light-emitting diodes
Full visible range covering InP/ZnS core-shell nanocrystals with high photometric performance have been prepared. Making use of these nanocrystals, we demonstrate a white quantum dot LED with a high color rendering index of 91.
Improved InGaN/GaN light-emitting diodes with a p-GaN/n-GaN/p-GaN/n-GaN/p-GaN current-spreading layer
This work reports both experimental and theoretical studies on the InGaN/GaN light-emitting diodes (LEDs) with optical output power and external quantum efficiency (EQE) levels substantially enhanced by incorporating ...
UV-blocking ZnO nanostructure anti-reflective coatings
In this paper, we apply finite difference time domain simulation to determine the absorptance and reflectance of ZnO nanowire and nanohole array structures for an efficient UV-blocking anti-reflective coating. Comparing ...
Stable and low-threshold optical gain in CdSe/CdS quantum dots : an all-colloidal frequency up-converted laser
An all-solution processed and all-colloidal laser is demonstrated using tailored CdSe/CdS core/shell quantum dots, which exhibit highly stable and low-threshold optical gain owing to substantially suppressed non-radiative ...
Large-area (> 50 cm × 50 cm), freestanding, flexible, optical membranes of Cd-free nanocrystal quantum dots
Colloidal semiconductor quantum dots (QDs) have been extensively explored for numerous applications ranging from optoelectronics to biotechnology. This strong demand for the colloidal QDs arises because of their favorable ...
Large-area semi-transparent light-sensitive nanocrystal skins
Large area and semi-transparent highly light sensitive nanocrystal skin is demonstrated via spray-coating nanocrystals on top of polyelectrolyte-polymers based on photogenerated potential buildup where no external bias is applied.
Observation of biexcitons in the presence of trions generated via sequential absorption of multiple photons in colloidal quantum dot solids
Multi exciton generation (MEG) and multi exciton recombination (MER) in semiconductor quantum dots (QDs) have recently attracted significant scientific interest as a possible means to improve device efficiencies [1-5]. ...
Simultaneous enhancement of electron overflow reduction and hole injection promotion by tailoring the last quantum barrier in InGaN/GaN light-emitting diodes
A three-step graded undoped-InGaN layers embedded between the GaN last quantum barrier layer and the p-AlGaN electron blocking layer was proposed and its effect on the performance of InGaN/GaN light-emitting diodes was ...
Advances in the LED materials and architectures for energy-saving solid-state lighting toward “lighting revolution”
In this paper, we review the recent developments (in years 2010–2011) of energy-saving solid-state lighting. The industry of white light-emitting diodes (LEDs) has made significant progress, and today, white LED market is ...