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Engineers achieve record 31% efficiency in red quantum LEDs for enhanced display color and brightness

A research team led by the School of Engineering of The Hong Kong University of Science and Technology (HKUST) has made significant advances in quantum rod light-emitting diodes (QR-LEDs), setting record-high efficiency level for red QR-LEDs. This innovation is poised to revolutionize next-generation display and lighting technologies, offering smartphone and television users a vibrant and enhanced visual experience. The research is published in the journal Advanced Materials.

LEDs have been widely used in for decades. Recent developments in have given rise to quantum dot LEDs (QD-LEDs) and QR-LEDs. QD-LEDs offer superior color purity (color vividness) and higher brightness compared to current mainstream LEDs. However, outcoupling efficiency has now become the primary obstacle, as it sets a fundamental ceiling for external quantum efficiency (EQE), thereby hindering any further performance improvements.

Quantum rods, on which QR-LEDs are based, are a type of elongated anisotropic nanocrystals with unique optical properties that can be engineered to optimize the light emission direction and ultimately improve outcoupling efficiency. However, QR-LEDs encounter two significant technical challenges: first, the ratio of emitted to absorbed photons (photoluminescence quantum yield) is relatively low after the material absorbs photons; second, there is a substantial leakage current due to poor thin-film quality.

Frontiers: Consciousness science: where are we, where are we going, and what if we get there?

The first distinction is between the notion of the level of consciousness and the notion of the contents of consciousness. In the first sense, consciousness is a property associated with an entire organism (a creature) or system: one is conscious (for example, when in a normal state of wakefulness) or not (for example, when in deep dreamless sleep or a coma). There is an ongoing vibrant debate about whether one should think of levels of consciousness as degrees of consciousness or whether they are best characterized in terms of an array of dimensions (11) or as “global states” (12). In the second sense, consciousness is always consciousness of something: our subjective experience is always “contentful”—it is always about something, a property philosophers call intentionality (3, 13). Here, again, there is some debate over the terms, for example, whether there can be fully contentless global states of consciousness (14) and whether consciousness levels (or global states) and contents are fully separable (11, 15).

The second distinction is between perceptual awareness and self-awareness (note that in this article, we use the terms consciousness and awareness interchangeably). Perceptual awareness simply refers to the fact that when we are perceptually aware, we have a qualitative experience of the external world and of our bodies within it (though of course, some perceptual experiences can be entirely fictive, such as when dreaming, vividly imagining, or hallucinating). Importantly, mere sensitivity to sensory information is not sufficient to be considered as perceptual awareness: the carnivorous plant Dionaea muscipula and the camera on your phone are both sensitive to their environment, but we have little reason to think that either has perceptual experiences. Thus, mere sensitivity is not sufficient for perceptual awareness, as it does not necessarily feel like something to be sensitive. This experiential character is precisely what makes the corresponding sensation a conscious sensation (16).

Ultracompact semiconductor could power next-gen AI and 6G chips

A research team, led by Professor Heein Yoon in the Department of Electrical Engineering at UNIST has unveiled an ultra-small hybrid low-dropout regulator (LDO) that promises to advance power management in advanced semiconductor devices. This innovative chip not only stabilizes voltage more effectively, but also filters out noise—all while taking up less space—opening new doors for high-performance system-on-chips (SoCs) used in AI, 6G communications, and beyond.

The new LDO combines analog and digital circuit strengths in a hybrid design, ensuring stable power delivery even during sudden changes in current demand—like when launching a game on your smartphone—and effectively blocking unwanted noise from the power supply.

What sets this development apart is its use of a cutting-edge digital-to-analog transfer (D2A-TF) method and a local ground generator (LGG), which work together to deliver exceptional voltage stability and noise suppression. In tests, it kept voltage ripple to just 54 millivolts during rapid 99 mA current swings and managed to restore the voltage to its proper level in just 667 nanoseconds. Plus, it achieved a power supply rejection ratio (PSRR) of −53.7 dB at 10 kHz with a 100 mA load, meaning it can effectively filter out nearly all noise at that frequency.

Scientists smash record in stacking semiconductor transistors for large-area electronics

King Abdullah University of Science and Technology (KAUST; Saudi Arabia) researchers have set a record in microchip design, achieving the first six-stack hybrid CMOS (complementary metal-oxide semiconductor) for large-area electronics. With no other reported hybrid CMOS exceeding two stacks, the feat marks a new benchmark in integration density and efficiency, opening possibilities in electronic miniaturization and performance.

A paper detailing the team’s research appears in Nature Electronics.

Among microchip technologies, CMOS microchips are found in nearly all electronics, from phones and televisions to satellites and medical devices. Compared with conventional silicon chips, hybrid CMOS microchips hold greater promise for large-area electronics. Electronic miniaturization is crucial for flexible electronics, smart health, and the Internet of Things, but current design approaches are reaching their limits.

Retina e-paper promises screens ‘visually indistinguishable from reality’

In what could be an industry shifting breakthrough, researchers have created a screen about the size of a human pupil with a resolution that breaks through the limits of pixels. The invention could radically change virtual reality and other applications.

While most video screens such as those on our phones, TVs, and stadium jumbotrons seem to improve in resolution on a monthly basis, there has been an issue in improving the resolution of the tiny screens required in virtual reality apps. The problem is that as the screen moves closer to the human eye, the pixels that comprise it need to get smaller and smaller. Yet, if pixels get too small, their function starts to degrade and the image suffers. On a micro-LED screen, for example, pixels can’t get much smaller than one micrometer wide before losing their ability to render a clear, crisp image.

So instead of relying on pixels, researchers from Chalmers University of Technology, the University of Gothenburg and Uppsala University in Sweden turned to a different technique. They created what they’ve termed “metapixels” out of tungsten oxide, a material that can switch from being an insulator to a metal based on its electrical state. The metapixels reflect light differently based on their size and how they’re arranged, and can be manipulated by an electrical current. In a way, they function much like the pigments in bird’s feathers, which can take on different colors based on how the light is hitting them.

Researchers help break thermal conductivity barrier with boron arsenide discovery

University of Houston researchers have made a discovery in thermal conductivity that overturns an existing theory that boron arsenide (BAs) couldn’t compete with the heat conduction of a diamond.

Instead, the team found that high-quality crystals can achieve exceeding 2,100 watts per meter per Kelvin (W/mK) at room temperature—possibly higher than diamond, which has been considered the best heat conductor among isotropic materials.

Published in Materials Today, this research challenges existing theories and could reshape our understanding of heat-conducting materials. It could also bring forth a new semiconductor material with much better thermal management in cell phones, high-powered electronics and .

Ultra-compact semiconductor could power next-gen AI and 6G chips

A research team, led by Professor Heein Yoon in the Department of Electrical Engineering at UNIST has unveiled an ultra-small hybrid low-dropout regulator (LDO) that promises to advance power management in advanced semiconductor devices. This innovative chip not only stabilizes voltage more effectively, but also filters out noise—all while taking up less space—opening new doors for high-performance system-on-chips (SoCs) used in AI, 6G communications, and beyond.

The new LDO combines analog and digital circuit strengths in a hybrid design, ensuring stable power delivery even during sudden changes in current demand—like when launching a game on your smartphone—and effectively blocking unwanted noise from the power supply.

What sets this development apart is its use of a cutting-edge digital-to-analog transfer (D2A-TF) method and a local ground generator (LGG), which work together to deliver exceptional voltage stability and noise suppression. In tests, it kept voltage ripple to just 54 millivolts during rapid 99 mA current swings and managed to restore the voltage to its proper level in just 667 nanoseconds. Plus, it achieved a rejection ratio (PSRR) of −53.7 dB at 10 kHz with a 100 mA load, meaning it can effectively filter out nearly all noise at that frequency.

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