Toggle light / dark theme

Get the latest international news and world events from around the world.

Log in for authorized contributors

Heavy fermions emerge at an atomic-layer interface, unlocking new ways to design quantum materials

A research team led by the University of Osaka has directly observed, for the first time, an unusual heavy-fermion state forming at the boundary between a one-atom-thick material and a metal. Such states are closely linked to exotic quantum phenomena, including unconventional superconductivity, and the finding opens new possibilities for designing quantum materials through their interfaces.

The researchers created a high-quality, one-atom-thick layer of ytterbium–copper (YbCu₂) on a copper crystal and examined how electrons behaved across the interface using intense synchrotron light. Their measurements showed that electrons localized in the atomic layer interact with mobile electrons in the underlying copper to form the heavy-fermion state.

The measurements revealed two distinct heavy-fermion states. One was confined mainly to the two-dimensional YbCu₂ layer, while the other extended into the three-dimensional copper substrate. Crucially, the latter arose from hybridization between localized Yb 4f electrons in the atomic layer and mobile conduction electrons in the underlying copper, providing direct evidence of an interfacial heavy-fermion state.

A gamma-ray burst’s engine stayed active for nearly a month, breaking the previous record

Astronomers have observed the longest-lasting central engine activity ever recorded from a gamma-ray burst. The burst occurred at a redshift of 0.8577, and the activity lasted about 27 days in the burst’s own rest frame—around 20 days longer than the previous record. The paper, posted to the arXiv preprint server on Sept. 18, explores different mechanisms that could be powering this puzzling burst.

Gamma-ray bursts (GRBs) are among the most energetic explosions in the universe, typically linked to the collapse of massive stars into black holes (producing long-duration GRBs, often with an accompanying supernova) or the merger of neutron stars (producing short-duration GRBs).

Ultra-long GRBs are a rare subclass of gamma-ray bursts in which the object driving or powering the explosion stays active longer than in typical bursts. Only a handful of confirmed examples exist, and their cause remains debated. Understanding what powers these rare ultra-long bursts helps explain how massive stars die and what kind of compact object is left behind.

Hit songs fade faster from the Billboard charts than albums

Favorite songs can stay with us for a lifetime, but their shelf life on the music charts is fleetingly short. Tracks that shoot up the U.S. Billboard charts may flood the airwaves for a short while, but just a few weeks later, they have vanished. The outlook for albums is far more enduring, according to a new paper published in the journal Royal Society Open Science.

A research team led by Arthur A. B. Pessa at the State University of Maringá in Brazil analyzed nearly seven decades of U.S. music history. They tracked every entry on the weekly Billboard Hot 100 song chart since 1958 and the Billboard 200 album chart since 1967 through January 2026.

The team wanted to know how long releases stayed on the charts, how often they dropped off and returned, and how their positions shifted over time.

Francis Halzen wins Nobel Prize in physics for work on mysterious ghost particles called neutrinos

Francis Halzen won the Nobel Prize in physics on Tuesday for his efforts to demystify a rare group of neutrinos, tiny cosmic particles that scientists believe offer clues to how the universe evolved.

“It was a great surprise and I obviously didn’t expect it,” Halzen said, speaking to the committee by phone from Italy, in a call broadcast at the news conference to announce the winner.

Halzen said it was predicted before that he would win the Nobel Prize but the announcement still made him feel “strange.”

Simulated moon soil and recyclable thermoplastics could help build future space infrastructure

Transporting material from Earth to the moon is an expensive proposition: By some estimates, moving a single kilogram (2.2 pounds) can cost more than $1 million. Any plan to build a permanent human habitat up there will depend on bringing that sky-high cost down.

Engineers and planners have long eyed lunar regolith —the small, sharp rocky shards and dust that cover the moon’s surface—as an invaluable and abundant printing ingredient. Now, a Concordia study shows how combining regolith with recycled high-performance plastic could be used to 3D print components onsite for future lunar missions.

The researchers created a composite using lunar regolith simulant and a recycled, high-performance thermoplastic known as poly(ether ketone ketone), or PEKK. They then used the composite to successfully 3D print components designed to absorb energy and deform under load rather than serve as permanent structural components. These structures, known as sacrificial structures, were used to measure how well the composite could withstand stresses similar to those the landing mechanism of a lunar module would have to absorb on impact.

Reading beyond the peaks: Optical analysis decodes spectral complexity in twisted semiconductor layers

A study from the Research Center for Materials Nanoarchitectonics (MANA), one of the centers under the National Institute for Materials Science (NIMS), presents a new method to reveal hidden material disorder reflected in complex photoluminescence spectra, paving the way for new optical diagnostics of material disorder in two-dimensional semiconductors and related light-emitting materials.

When two ultrathin semiconductor layers, such as molybdenum diselenide and tungsten diselenide (MoSe2/WSe2), are stacked with a slight twist, they form a repeating pattern called a moiré heterostructure. These structures have unusual light-emitting properties, featuring a complex landscape of photoluminescence spectra across their surface.

While scientists often analyze materials by looking at the individual peaks of their emission spectra, moiré heterostructures produce spectra with many overlapping peaks whose origins are difficult to explain individually.

New chip-based frequency combs demonstrate potential for portable atomic clocks

The world would look radically different without rulers and measuring tapes that fit into a pocket. Carpenters, fashion designers and engineers rely on these trusty tools to check the size of everything from a wooden board to a fabric swatch. But physicists who work with light lack that same convenience for one of the basic measurements of their craft. They routinely need to measure and compare the frequencies—colors—of the light waves they are using.

To date, they have lacked a similarly pocket-sized tool for routine measurements, and they make do with cumbersome equipment that crowds their lab space and is far from portable.

The standard tool for measuring the frequency of light is called an optical frequency comb. This device produces a rainbow of different frequencies of light, all spaced at regular intervals like the tick marks on a measuring tape. Frequency combs let researchers measure the difference between distinct frequencies and are crucial for many experiments and measurements that use light.

Chernobyl particles reveal unexpectedly stable nuclear fuel after 40 years

Four decades after the 1986 nuclear disaster, researchers at Leibniz University Hannover and the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) examined six tiny, highly radioactive fragments that were released from the destroyed reactor in Ukraine in the wake of the incident. Analyses show that these “hot particles” are far more stable than had previously been assumed. The findings could allow for more precise assessments of the health risks posed by such radioactive particles. The paper is published in the Journal of Hazardous Materials.

The explosions hurled massive amounts of debris from the nuclear reactor, radioactive dust particles still contaminate the soil around the disaster area, known today as Chernobyl. Measuring only 8 to 50 micrometers, they remain highly radioactive even after 40 years. Even today, people may enter the affected areas only while wearing protective suits.

“There are three classes of these particles,” explains Tobias Weissenborn, a physicist and doctoral candidate at Leibniz University Hannover. “First, there are particles that are chemically and physically still very similar to the nuclear fuel uranium dioxide. Then, there are particles that are partially or fully encased in, or completely fused with, their zirconium layer.”

Stretching boosts thermal and electrical conductivity in new nanocomposite

A joint research team led by professors Seunghyun Baik and Joonmyung Choi from the School of Mechanical Engineering at Sungkyunkwan University (SKKU) has developed a new nanocomposite material whose electrical and thermal conductivities increase as it is stretched. The team successfully applied it to stable heat dissipation for foldable phones.

The research is published in Advanced Functional Materials.

Smartphones and electronic devices generate significant heat during operation, which can cause performance throttling or shorten device lifespan if not properly cooled. Next-generation flexible electronics that bend or stretch face particular challenges because heat cannot easily escape during deformation. Typically, stretching a material increases the distance between embedded particles, which reduces both thermal and electrical conduction. However, the research team designed a material that overturns this conventional understanding.

Blue-light labeling uncovers unexpected protein partners of folded DNA structures

DNA can be more than just a double helix. When four strands are folded into a compact bundle, they form a G-quadruplex (G4). These bundles form in guanine-rich regions across the genome, including telomeres at the ends of chromosomes and the control regions of genes, where the proteins that dock onto them help decide which genes are switched on. G4 does not act the same way everywhere. What it does depends on where it forms and which proteins bind to it. This is why understanding the interactions surrounding G4 is so important.

Biochemical assays give us more information about the intricacies of these interactions. These assays assess how DNA and proteins interact during processes such as DNA replication, transcription and repair. However, previous assays haven’t been able to capture the full picture.

A team led by Kazumitsu Onizuka and Shinichi Sato of Tohoku University, with Takanori Oyoshi of Shizuoka University, has developed a photocatalytic proximity labeling method that overcomes previous pitfalls and captures partners that earlier methods missed. The technique also revealed hexokinase-1 to be an unexpected player in these interactions.

/* */