The instrument uses light to move atoms to measure incredibly small forces.
A self-correcting atom interferometer amplifies signals, aiding detection of ultra-weak forces from dark matter, dark energy, and waves.
Scientists have accidentally discovered a particle that has mass when it’s traveling in one direction, but no mass while traveling in a different direction. Known as semi-Dirac fermions, particles with this bizarre behavior were first predicted 16 years ago.
The discovery was made in a semi-metal material called ZrSiS, made up of zirconium, silicon and sulfur, while studying the properties of quasiparticles. These emerge from the collective behavior of many particles within a solid material.
“This was totally unexpected,” said Yinming Shao, lead author on the study. “We weren’t even looking for a semi-Dirac fermion when we started working with this material, but we were seeing signatures we didn’t understand – and it turns out we had made the first observation of these wild quasiparticles that sometimes move like they have mass and sometimes move like they have none.”
Photosynthesis is one of the most efficient natural processes for converting light energy from the sun into chemical energy vital for life on earth. Proteins called photosystems are critical to this process and are responsible for the conversion of light energy to chemical energy.
Combining one kind of these proteins, called photosystem I (PSI), with platinum nanoparticles, microscopic particles that can perform a chemical reaction that produces hydrogen — a valuable clean energy source — creates a biohybrid catalyst. That is, the light absorbed by PSI drives hydrogen production by the platinum nanoparticle.
In a recent breakthrough, researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Yale University have determined the structure of the PSI biohybrid solar fuel catalyst. Building on more than 13 years of research pioneered at Argonne, the team reports the first high-resolution view of a biohybrid structure, using an electron microscopy method called cryo-EM. With structural information in hand, this advancement opens the door for researchers to develop biohybrid solar fuel systems with improved performance, which would provide a sustainable alternative to traditional energy sources.
At just a few atoms of thickness, 2D materials offer revolutionary possibilities for new technologies that are microscopically sized but have the same capabilities as existing machines.
Florida State University researchers have unlocked a new method for producing one class of 2D material and for supercharging its magnetic properties. The work was published in Angewandte Chemie.
Experimenting on a metallic magnet made from the elements iron, germanium and tellurium and known as FGT, the research team made two breakthroughs: a collection method that yielded 1,000 times more material than typical practices, and the ability to alter FGT’s magnetic properties through a chemical treatment.
Chondritic meteorites (chondrites) are some of the oldest rocks in our solar system, forming 4.5 billion years ago. Therefore, their primitive composition means that they offer a window into the origins of planet formation, particularly as their major elements (heavier than hydrogen and helium, including oxygen, silicon, magnesium, iron and nickel) closely reflect the sun’s photosphere composition.
Melting and clumped accumulation (accretion) of dust particles at high temperatures (up to 2,000 Kelvin [~1,727 °C]) in the protoplanetary disk formed crystallized silicate spheres known as chondrules, which further joined together to produce asteroids, the remnants of planetary genesis.
There are two main types, believed to have formed in the inner and outer solar system respectively: ordinary chondrites are composed of up to 90% chondrules, while carbonaceous chondrites have only 20–50% chondrules within a background matrix.
Researchers at Tohoku University and the University of California, Santa Barbara, have developed new computing hardware that utilizes a Gaussian probabilistic bit made from a stochastic spintronics device. This innovation is expected to provide an energy-efficient platform for power-hungry generative AI.
As Moore’s Law slows down, domain-specific hardware architectures—such as probabilistic computing with naturally stochastic building blocks—are gaining prominence for addressing computationally hard problems. Similar to how quantum computers are suited for problems rooted in quantum mechanics, probabilistic computers are designed to handle inherently probabilistic algorithms.
These algorithms have applications in areas like combinatorial optimization and statistical machine learning. Notably, the 2024 Nobel Prize in Physics was awarded to John Hopfield and Geoffrey Hinton for their groundbreaking work in machine learning.
The sun, the essential engine that sustains life on Earth, generates its tremendous energy through the process of nuclear fusion. At the same time, it releases a continuous stream of neutrinos—particles that serve as messengers of its internal dynamics. Although modern neutrino detectors unveil the sun’s present behavior, significant questions linger about its stability over periods of millions of years—a timeframe that spans human evolution and significant climate changes.
Finding answers to this is the goal of the LORandite EXperiment (LOREX) that requires a precise knowledge of the solar neutrino cross section on thallium. This information has now been provided by an international collaboration of scientists using the unique facilities at GSI/FAIR’s Experimental Storage Ring ESR in Darmstadt to obtain an essential measurement that will help to understand the long-term stability of the sun. The results of the measurements have been published in the journal Physical Review Letters.
LOREX is the only long-time geochemical solar neutrino experiment still actively pursued. Proposed in the 1980s, it aims to measure solar neutrino flux averaged over a remarkable four million years, corresponding to the geological age of the lorandite ore.
Three distinct topological degrees of freedom are used to define all topological spin textures based on out-of-plane and in-plane spin configurations: the topological charge, representing the number of times the magnetization vector m wraps around the unit sphere; the vorticity, which quantifies the angular integration of the magnetic moment along the circumferential direction of a domain wall; and the helicity, defining the swirling direction of in-plane magnetization.
Electrical manipulation of these three degrees of freedom has garnered significant attention due to their potential applications in future spintronic devices. Among these, the helicity of a magnetic skyrmion—a critical topological property—is typically determined by the Dzyaloshinskii-Moriya interaction (DMI). However, controlling skyrmion helicity remains a formidable challenge.
A team of scientists led by Professor Yan Zhou from The Chinese University of Hong Kong, Shenzhen, and Professor Senfu Zhang from Lanzhou University successfully demonstrated a controllable helicity switching of skyrmions using spin-orbit torque, enhanced by thermal effects.
Assuming dark matter exists, its interactions with ordinary matter are so subtle that even the most sensitive instruments cannot detect them. In a new study, Northwestern University physicists now introduce a highly sensitive new tool, which amplifies incredibly faint signals by 1,000 times—a 50-fold improvement over what was previously possible.
Called an atom interferometer, the incredibly precise tool manipulates atoms with light to measure exceptionally tiny forces. But, unlike other atom interferometers, which are limited by the imperfections in the light itself, the new tool self-corrects for these imperfections to reach record-breaking levels of precision.
By boosting imperceptible signals to perceptible levels, the technological advance could help scientists who are hunting for ultra-weak forces emitted from a variety of evasive phenomena, including dark matter, dark energy and gravitational waves in unexplored frequency ranges.
Scientists have made a groundbreaking discovery of a new extinct species of coelacanth, thanks to an unexpected tool: a particle accelerator. This cutting-edge technology allowed scientists to analyze 240-million-year-old fossils in unprecedented detail. The new species sheds light on ancient fish behavior and anatomy in ways never before possible.
