X-rays show birth of semiconductor for blue LEDs

Gallium nitride is the second most important semiconductor material after silicon

28-Feb-2020 - Using a special pressure furnace, an international team of researchers has analysed the initial stages of the growth of the semiconductor gallium nitride with X-ray light. The observations show for the first time the atomic structure of the interface of the semiconductor material with liquid ...

New light shed on intensely studied material

21-Jan-2019 - The organic polymer PEDOT is probably one of the world's most intensely studied materials. Despite this, researchers at Linköping University have now demonstrated that the material functions in a completely different manner than previously believed. The result has huge significance in many fields ...

Smart Fluorescent Dyes

Modulating photo- and electroluminescence in a stimuli-responsive molecular dye

17-Aug-2018 - Controlling the excited electronic states in luminescent systems remains a challenge in the development of fluorescent and phosphorescent dyes. Now, scientists in Japan have developed a unique organic fluorophore that changes its emission color without loss of efficiency when externally ...

Quantum Dot White LEDs Achieve Record Efficiency

16-Jul-2018 - Researchers have demonstrated nanomaterial-based white-light-emitting diodes (LEDs) that exhibit a record luminous efficiency of 105 lumens per watt. Luminous efficiency is a measure of how well a light source uses power to generate light. With further development, the new LEDs could reach ...

A better way to control crystal vibrations

23-May-2018 - The vibrational motion of an atom in a crystal propagates to neighboring atoms, which leads to wavelike propagation of the vibrations throughout the crystal. The way in which these natural vibrations travel through the crystalline structure determine fundamental properties of the material. For ...

Extremely bright and fast light emission

12-Jan-2018 - An international team of researchers from ETH Zurich, IBM Research Zurich, Empa and four American research institutions have found the explanation for why a class of nanocrystals that has been intensively studied in recent years shines in such incredibly bright colours. The nanocrystals contain ...

A spectroscopic 'science camera' system for smartphones

15-Sep-2017 - The latest versions of most smartphones contain at least two and sometimes three built-in cameras. Researchers at the University of Illinois would like to sell mobile device manufactures on the idea of adding yet another image sensor as a built-in capability for health diagnostic, environmental ...

Organic photodiodes – more economical detectors for the NIR region

07-Sep-2017 - The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP will be introducing a new generation of organic photodiodes on silicon substrates (OPD-on-silicon) during the SEMI European Imaging & Sensors Summit 2017. Optical sensors are pervasive. Domestic life as well ...

Bright thinking leads to breakthrough in nuclear threat detection science

03-Jul-2017 - Taking inspiration from an unusual source, a Sandia National Laboratories team has dramatically improved the science of scintillators -- objects that detect nuclear threats. According to the team, using organic glass scintillators could soon make it even harder to smuggle nuclear materials ...

Crystal clear imaging

Infrared brings to light nanoscale molecular arrangement

17-Oct-2016 - Detailing the molecular makeup of materials -- from solar cells to organic light-emitting diodes (LEDs) and transistors, and medically important proteins -- is not always a crystal-clear process. To understand how materials work at these microscopic scales, and to better design materials to ...