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Researchers have resolved the mechanism of exciton fission, which could increase solar-to-electricity efficiency by one-third, potentially revolutionizing photovoltaic technology.

Photovoltaics, the conversion of light to electricity, is a key technology for sustainable energy. Since the days of Max Planck and Albert Einstein, we know that light as well as electricity are quantized, meaning they come in tiny packets called photons and electrons. In a solar cell, the energy of a single photon.

A photon is a particle of light. It is the basic unit of light and other electromagnetic radiation, and is responsible for the electromagnetic force, one of the four fundamental forces of nature. Photons have no mass, but they do have energy and momentum. They travel at the speed of light in a vacuum, and can have different wavelengths, which correspond to different colors of light. Photons can also have different energies, which correspond to different frequencies of light.

The algorithm combines classical beam physics equations with machine-learning techniques to reduce the need for extensive data processing.

When the linear accelerator at SLAC National Accelerator Laboratory is operational, groups of approximately one billion electrons travel through metal pipes at almost the speed of light. These electron groups form the accelerator’s particle beam, which is utilized to investigate the atomic behavior of molecules, innovative materials, and numerous other subjects.

However, determining the actual appearance of a particle beam as it moves through an accelerator is challenging, leaving scientists with only a rough estimate of how the beam will behave during an experiment.

2D materials, which are finer than even the thinnest onionskin paper, have garnered significant attention due to their remarkable mechanical attributes. However, these properties dissapate when the materials are layered, thus restricting their practical applications.

“Think of a graphite pencil,” says Teng Li, Keystone Professor at the University of Maryland’s (UMD) Department of Mechanical Engineering. “Its core is made of graphite, and graphite is composed of many layers of graphene.

Graphene is an allotrope of carbon in the form of a single layer of atoms in a two-dimensional hexagonal lattice in which one atom forms each vertex. It is the basic structural element of other allotropes of carbon, including graphite, charcoal, carbon nanotubes, and fullerenes. In proportion to its thickness, it is about 100 times stronger than the strongest steel.

Scientists have invented a simple metallic coating treatment for clothing or wearable textiles, which can repair itself, repel bacteria, and even monitor a person’s electrocardiogram (ECG) heart signals.

This is according to a press release by Flinders University published last month.

The inventors of the new coating say the conductive circuits created by liquid metal (LM) particles can transform wearable electronics due to the fact that the ‘breathable’ electronic textiles have special connectivity powers to ‘autonomously heal’ themselves even when cut.

A small team of chemists at the Russian Academy of Sciences, has found that metal atoms, not nanoparticles, play the key role in catalysts used in fine organic synthesis. In the study, reported in the Journal of the American Chemical Society, the group used multiple types of electron microscopy to track a region of a catalyst during a reaction to learn more about how it was proceeding.

Prior research has shown that there are two main methods for studying a reaction. The first is the most basic: As ingredients are added, the reaction is simply observed and/or measured. This can be facilitated through use of high-speed cameras. This approach will not work with nanoscale reactions, of course. In such cases, chemists use a second method: They attempt to capture the state of all the components before and after the reaction and then compare them to learn more about what happened.

This second approach leaves much to be desired, however, as there is no way to prove that the objects under study correspond with one another. In recent years, have been working on a new approach: Following the action of a single particle during the reaction. This new method has proven to have merit but it has limitations as well—it also cannot be used for reactions that occur in the nanoworld. In this new effort, the researchers used multiple types of electron microscopy coupled with .

Researchers in Germany and the U.S. have shown for the first time that terahertz (THz) light pulses can stabilize ferromagnetism in a crystal at temperatures more than three times its usual transition temperature. As the team reports in Nature, using pulses just hundreds of femtoseconds long (a millionth of a billionth of a second), a ferromagnetic state was induced at high temperature in the rare-earth titanate YTiO3 which persisted for many nanoseconds after the light exposure. Below the equilibrium transition temperature, the laser pulses still strengthened the existing magnetic state, increasing the magnetization up to its theoretical limit.

Using light to control magnetism in solids is a promising platform for future technologies. Today’s computers mainly rely on the flow of electrical charge to process information. Moreover, digital memory storage devices make use of magnetic bits that must be switched external magnetic fields. Both of these aspects limit the speed and energy efficiency of current computing systems. Using light instead to optically switch memory and computing devices could revolutionize processing speeds and efficiency.

YTiO3 is a transition metal oxide that only becomes ferromagnetic, with properties resembling those of a fridge magnet, below 27 K or −246°C. At these low temperatures, the spins of the electrons on the Ti atoms align in a particular direction. It is this collective ordering of the spins which gives the material as a whole a macroscopic magnetization and turns it ferromagnetic. In contrast, at temperatures above 27 K, the individual spins fluctuate randomly so that no ferromagnetism develops.

Inside a lab, scientists marvel at a strange state that forms when they cool down atoms to nearly absolute zero. Outside their window, trees gather sunlight and turn them into new leaves. The two seem unrelated—but a new study from the University of Chicago suggests that these processes aren’t so different as they might appear on the surface.

The study, published in PRX Energy on April 28, found links at the between photosynthesis and exciton condensates—a strange state of physics that allows energy to flow frictionlessly through a material. The finding is scientifically intriguing and may suggest new ways to think about designing electronics, the authors said.

“As far as we know, these areas have never been connected before, so we found this very compelling and exciting,” said study co-author Prof. David Mazziotti.

He thinks about Robert Oppenheimer and the Manhattan Project that led to the atomic bomb, Hiroshima, and Nagasaki, and the current state of mutually assured destruction (MAD). It started with a science experiment to split the atom and soon the genie was released from the bottle.

I think of the arrival of generalized AI like ChatGPT as being equivalent to the revolution brought on by the invention of movable type and the printing press. Would the Reformation in Europe have happened without it? Would Europe’s rise to world dominance in the 18th and 19th centuries have resulted? The printing press genie uncorked led to a generalized knowledge revolution with both good and bad consequences.

The future uncorked AI genie with no guidance from us could, in answering the question I asked at the beginning of this posting, see humanity as the greatest threat to life on the planet and act accordingly if we don’t gain control over it.

Researchers at Caltech have discovered a new phenomenon, “collectively induced transparency” (CIT), where light passes unimpeded through groups of atoms at certain frequencies. This finding could potentially improve quantum memory systems.

A newly discovered phenomenon dubbed “collectively induced transparency” (CIT) causes groups of atoms to abruptly stop reflecting light at specific frequencies.

CIT was discovered by confining ytterbium atoms inside an optical cavity—essentially, a tiny box for light—and blasting them with a laser. Although the laser’s light will bounce off the atoms up to a point, as the frequency of the light is adjusted, a transparency window appears in which the light simply passes through the cavity unimpeded.