Category Technology/Electronics

Quantum Dot White LEDs achieve Record Efficiency

Researchers created nanomaterial-based white LEDs that exhibit a record high efficiency thanks to quantum dots that are suspended in solution rather than embedded in a solid. The new LEDs could offer an energy-efficient lighting source for homes, offices and televisions. Credit: Sedat Nizamoglu, Koç University

Researchers created nanomaterial-based white LEDs that exhibit a record high efficiency thanks to quantum dots that are suspended in solution rather than embedded in a solid. The new LEDs could offer an energy-efficient lighting source for homes, offices and televisions.
Credit: Sedat Nizamoglu, Koç University

Novel approach to white LEDs could lead to more energy-efficient lighting. 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...

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The Perfect Terahertz Beam – thanks to the 3D Printer

When the screens are inserted into the beam, the desired patterns emerge: a cross or the logo of TU Wien.
Credit: TU Wien

Researchers succeed in shaping terahertz beams with extremely high precision. Terahertz radiation can be used for a wide variety of applications and is used today for airport security checks just as much as it is for material analysis in the lab. The wavelength of this radiation is in the millimetre range, meaning that it is significantly larger than the wavelength of visible light. It also requires specialised techniques to manipulate the beams and get them into the right shape...

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Generating Electrical Power from Waste Heat

This tiny silicon-based device developed at Sandia National Laboratories can catch and convert waste heat into electrical power. The rectenna, short for rectifying antenna, is made of common aluminum, silicon and silicon dioxide using standard processes from the integrated circuit industry. Credit: Photo by Randy Montoya/Sandia National Laboratories

New solid-state silicon device may one day power space missions. Researchers have developed a tiny silicon-based device that can harness what was previously called waste heat and turn it into DC power. Directly converting electrical power to heat is easy. It regularly happens in your toaster, that is, if you make toast regularly. The opposite, converting heat into electrical power, isn’t so easy.

“We have developed a new method for essentially recovering energy from waste heat. Car engines produce a lot of heat and that heat is just waste, right? So imagine if you could convert that engine heat into electrical power for a hybrid car. This is the first step in that direction, but much more work needs to be done,” said Paul Davids, a physicist and the principal investigator for the study...

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Semiconductor Quantum Transistor Opens the door for Photon-based Computing

Researchers demonstrate the first single-photon transistor using a semiconductor chip. They used a single photon, stored in a quantum memory, to toggle the state of other photons. Credit: E. Edwards/Joint Quantum Institute

Researchers have demonstrated the first single-photon transistor using a semiconductor chip. Transistors are tiny switches that form the bedrock of modern computing; billions of them route electrical signals around inside a smartphone, for instance. Quantum computers will need analogous hardware to manipulate quantum information. But the design constraints for this new technology are stringent, and today’s most advanced processors can’t be repurposed as quantum devices. That’s because qubits, have to follow different rules laid out by quantum physics.

Scientists can use ...

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