Soon, our devices will get power from the light around us and send information at incredible speeds while being safer and more efficient. Here’s a look at what’s new in photonics at CES 2024.
A team of Chinese researchers used a novel theory to invent a new type of ultrathin optical crystal with high energy efficiency, laying the foundation for next-generation laser technology.
Prof. Wang Enge from the School of Physics, Peking University, recently told Xinhua that the Twist Boron Nitride (TBN) made by the team, with a micron-level thickness, is the thinnest optical crystal currently known in the world. Compared with traditional crystals of the same thickness, its energy efficiency is raised by 100 to 10,000 times.
Wang, also an academician of the Chinese Academy of Sciences, said this achievement is an original innovation by China in the theory of optical crystals and has created a new field of making optical crystals with two-dimensional thin-film materials of light elements.
In this study, we conducted behavioral experiments and measured survival rates in local caves to minimize the impacts of factors other than light. Although energy-costly eyes were highly reduced or lost in cave-dwelling Leptonetela spiders, which spend their entire life cycles in the complete absence of light, our results demonstrated that they could detect light, and light cues may be used to avoid the perilously dry environment outside the cave. The annotation of core PPGs based on transcriptomic data suggests that cave-dwelling Leptonetela spiders have retained a nearly complete set of PPGs as in the entrance spiders. The molecular evolutionary analysis showed strong purifying selection on PPGs of cave-dwelling Leptonetela spiders. Therefore, our study provides evidence supporting the hypothesis that the phototransduction system of cave-dwelling eyeless Leptonetela spiders may have been under purifying selection rather than being a phylogenetic relic. Our results thus refute the neutral hypothesis.
Leptonetela spiders are small cryptozoic spiders that build sheet webs for capturing prey in twilight or lightless environment, such as leaf litter, rotting logs, rock crevices, and caves (31). Light is suggested to be the primary selective force driving the evolution of eyes of cave animals, thus, eyes are often reduced or lost as cave preadaptation in many litter-dwelling arthropods (36–38). Leptonetela spiders have lost anterior median eyes that are generally involved in identifying and stalking prey in spiders, likely due to their twilight or lightless habitats. In addition, cave-dwelling Leptonetela spiders living in lightless deep caves exhibit various degrees of eye reduction (highly reduced or eyeless) compared to their entrance spider relatives that have six intact eyes. Thus, Leptonetela spiders provided an ideal system for studying the evolution of eyes and visual systems.
This study provides evidence demonstrating negative phototaxis in cave-dwelling spiders, a highly diverse group that plays a critical role in cave ecosystems as top predators (23). Negative phototaxis has frequently been found in other subterranean animals. For example, the cave-dwelling carrion beetle Ptomaphagus hirtus that has highly reduced eyes nonetheless displays strongly negative phototaxis and maintains a reduced but functional phototransduction system, as shown by transcriptomic data (13). However, Langille et al. (14) reported that five of six subterranean water beetles completely lacked phototactic responses, and the authors proposed negative phototaxis as a preadaptation to living in permanent darkness for ancestral cave-dwelling animals. We speculate that drought resistance may play an important role in the retention of PPGs in Leptonetela spiders.
In Iceland, scientists are planning to drill two boreholes to a reservoir of liquid rock. One will give us our first direct measurements of magma – the other could supercharge geothermal power.
The authors utilize both static and ultrafast terahertz conductivity spectroscopy to address the character of the superconducting state of infinite-layer nickelates.
Georgia Tech engineers are working to make fertilizer more sustainable—from production to productive reuse of the runoff after application—and a pair of new studies is offering promising avenues at both ends of the process.
In one paper, researchers have unraveled how nitrogen, water, carbon, and light can interact with a catalyst to produce ammonia at ambient temperature and pressure, a much less energy-intensive approach than current practice. The second paper describes a stable catalyst able to convert waste fertilizer back into nonpolluting nitrogen that could one day be used to make new fertilizer.
Significant work remains on both processes, but the senior author on the papers, Marta Hatzell, said they’re a step toward a more sustainable cycle that still meets the needs of a growing worldwide population.
Unless it is augmented with graphene, watching concrete dry might not be the most thrilling activity. Graphene was initially isolated in 2004 by scientists at The University of Manchester and has become iconic in materials research, with applications ranging from energy storage and water filtering to transportation and construction, including concrete.
A new future for cement is being facilitated by graphene. Soon, everyone will have the option to select the color, texture, and features that they want very soon. More significantly, though, and even more so than its practicality and beauty, the increasing global sustainability movement is rekindling interest in the possibilities of concrete enriched with graphene.
The building sector is confronted with a plethora of obstacles in light of Net Zero aims, and a viable path toward progress could be through the extensive integration of cutting-edge materials. Cement production accounts for 8–10% of worldwide CO2 emissions, making it one of the industries with the largest carbon footprints.
The project in Iceland will be the first ever attempt of drilling straight into the incredibly hard to find magma beneath the Earth’s surface.
One year after initial deliveries of solid-state battery prototypes to its automotive partners, QuantumScape is receiving additional praise from PowerCo – the battery-centric subsidiary of Volkswagen Group – for the potential of its technology. PowerCo recently completed an endurance test with QuantumScape’s solid-state cells and determined they can someday power EVs that can drive 500,000 kilometers with virtually no loss of range.
QuantumScape ($QS) is an advanced battery technology company that has been working for over a decade to develop scalable, energy-dense solid-state battery cells that can one-day power EVs that are safer, charge faster, and drive farther.
During QuantumScape’s tenure in solid-state battery development, Volkswagen Group has been a partner from early on and remains one of the startup’s largest investors. OEMs like Volkswagen have helped empower QuantumScape to continue its development and deliver some of the most promising solid-state battery technology in the industry.
Nanoparticles seem the future of electronics, at least until the next big thing.
Nano-engineered oxides are very important for the development of next-generation catalysts and microelectronics. Recently, metal exsolution from oxides has emerged as a promising nano-structuring tool to fabricate nanoparticle-decorated oxides. However, controlling the size, density, composition, and location of exsolved nanoparticles remains a challenge, limiting the ultimate performance achievable by these nanostructures.
The following nanoparticle production control was achieved: 1. ion sputtering can controllably reduce the size of surface exsolved nanoparticles down to 2 nm, which are among the smallest values reported in the literature thus far. 2. implanted metal ions can tailor the composition of nanoparticles exsolved both at the surface and in the bulk, providing a convenient and direct way to synthesize exsolved nanoparticles with alloyed compositions. 3. irradiation-induced lattice defects can catalyze the nucleation of nanoparticles, and this enables controlling the density and location of exsolved nanoparticles at specific sample locations using ion irradiation.
Continue reading “Controlling the Size, Composition and Dispersion of Metal Nanoparticles” »
