Notion Systems, a leading solution provider for industrial inkjet systems, announced that it had successfully installed an n.jet display system at Taiwan's Industrial Technology Research Institute (ITRI). The n.jet display system was developed in collaboration with MBraun/Germany and includes a fully integrated inert glove box solution that combines compact design with minimized nitrogen consumption.

ITRI is now using the new n.jet display system to research and develop novel QLED and OLED technologies. ITRI is looking to replace vapor deposition and vacuum coating with inkjet printing which could reduce the number of steps, increase material utilization and increase display quality.

UK-based OTFT-developer SmartKem and QD pioneer Nanosys announced a joint-development project to work on low-cost printed QD displays, that will combine SmartKem's printed organic TFT with Nanosys' quantum dots emitter platform.

Nanosys now refers to its emissive (electroluminescent) QD technology as nanoLED. Both technology platforms, the OTFT backplane and the NanoLED frontplane are solution-based, which could indeed result in a low-cost production process.

A research team from POSTECH in Korea developed a new method of arranging quantum dots based on the coffee ring effect. The researchers dispersed the QD particles in a solution, and then evaporated it to perform the deposition, which causes the particles to automatically assemble in certain areas, like the edges of a single solution drop.

The researchers report that the QDs self-arranged in the form of very fine pixels, as they used a V-shaped structure. The QDs are driven toward the inner tips of the V-shape and accumulate there. This enables the creation of QD-based pixels that are 20 times brighter compared to regular QDs deposited without the V-shaped structure, and have a high uniformity rate of over 98%.

An international team of researchers from Singapore, the US and China, led by a team at Singapore-MIT alliance SMART, discovered a new way to generate long-wavelength (red, orange and yellow) emitting quantum dots by taking advantage of intrinsic defects in semiconducting materials.

The researchers fabricate InGaN QDs that feature a significantly higher indium concentration by making use of pre-existing defects in InGaN materials. In this process, the coalescence of so-called V-pits, which result from naturally-existing dislocations in the material, directly forms indium-rich quantum dots, small islands of material that emit longer-wavelength light. Simply put, the material forms itself in a structure that includes small 'pyramids' - the tops of which are actually light-emitting quantum dots.

Researchers at Los Alamos National Laboratory (LANL) have assessed the status of research into colloidal quantum dot lasers with a focus on prospective electrically pumped devices, or laser diodes.

Their review analyzes the challenges for developing lasing with electrical excitation, and presents approaches to overcome them.

Last year, Poland-based Ergis Group launched an OLED encapsulation film platform called Ergis noDiffusion®. The company is currently testing its film solutions at customer sites in Asia, the EU and the US, and it is now starting to offer the same platform for the protection of quantum dot films (QD films) used in display and lighting applications.

These new films can be tuned to fit specific needs. Ergis can deploy its films on several substrate types, with varying film thickness, and the barrier properties can be tuned to be between 10-6 to 10-3. This means that custom films can be created to suit the specific sensitivity of the QDs for water vapor and to achieve specific product lifetime or other required properties.

Researchers from Northwestern University developed a perovskite quantum-dots based emitter that features high stability, self-healing and very high brightness.

Perovskite QDs can realize single photon emission at room temperature and have excellent optical properties. The research team has developed a unique spray-synthesis method to create these pQDs which greatly increases the contact area of two different solutions, making it possible to grow a uniform protective organic layer on the surface of the quantum dots.

Guest post by: Fraunhofer IAP & Fraunhofer CAN

"People push towards the light, not to see better, but to shine better" - Friedrich Wilhelm Nietzsche (1844 - 1900)

Quantum dots (QDs) represent the latest generation of hybrid inorganic-organic nanomaterials. They form a triad of inorganic nanotechnology, organic semiconductor technology and solution-based processability. The emission properties of inorganic, luminescent nanoparticles depend directly on the particle size. This size quantization effect makes it possible to control the band gap and thus the emission color of semiconductor materials. The target parameters are a high quantum yield of the luminescence as well as high stability and environmental compatibility.

A team of researchers, which included scientists from SLAC, Stanford, the University of California, Berkeley and DOE’s Lawrence Berkeley National Laboratory, recently explained a process that interferes with making quantum dots brighter - when attempting to increase the intensity of emitted light, heat is generated instead - reducing the dots’ light-producing efficiency. The results of this new work could have broad implications for developing future quantum and photonics technologies.

Image credit: Nature Communications/SLAC

In a QLED TV screen, dots absorb blue light and turn it into green or red. At the low energies where TV screens operate, this conversion of light from one color to another is virtually 100% efficient. But at the higher excitation energies required for brighter screens and other technologies, the efficiency drops sharply. Researchers theorized about why this happens, but no one had ever observed it at the atomic scale until now.

Scientists at the Chemistry and Physics Institutes of the University of Campinas (UNICAMP) in the state of São Paulo, Brazil, in collaboration with scientists at the University of Michigan in the United States, have provides insights into the fundamental physics of perovskite quantum dots.

Nanomaterials of perovskite dispersed in hexane and irradiated by laser. Light emission by these materials is intense thanks to resistance to surface defects (photo: Luiz Gustavo Bonato)

"We used coherent spectroscopy, which enabled us to analyze separately the behavior of the electrons in each nanomaterial in an ensemble of tens of billions of nanomaterials. The study is groundbreaking insofar as it combines a relatively new class of nanomaterials - perovskite - with an entirely novel detection technique," Lázaro Padilha Junior, principal investigator for the project on the Brazilian side, explained.