Phys.org Physics

• Ultracold atoms observed climbing a quantum staircase

  For the first time, scientists have observed the iconic Shapiro steps, a staircase-like quantum effect, in ultracold atoms.

• Research uncovers the telltale tail of black hole collisions

  When black holes collide, the impact radiates into space like the sound of a bell in the form of gravitational waves. But after the waves, there comes a second reverberation—a murmur that physicists have theorized but never observed.

• New image sensor breaks optical limits

  Imaging technology has transformed how we observe the universe—from mapping distant galaxies with radio telescope arrays to unlocking microscopic details inside living cells. Yet despite decades of innovation, a fundamental barrier has persisted: capturing high-resolution, wide-field images at optical wavelengths without cumbersome lenses or strict alignment constraints.

• Ultrafast fluorescence pulse technique enables imaging of individual trapped atoms

  Researchers at the ArQuS Laboratory of the University of Trieste (Italy) and the National Institute of Optics of the Italian National Research Council (CNR-INO) have achieved the first imaging of individual trapped cold atoms in Italy, introducing techniques that push single-atom detection into new performance regimes.

• Journey to the center of a quantized vortex: How microscopic mutual friction governs superfluid dissipation

  Step inside the strange world of a superfluid, a liquid that can flow endlessly without friction, defying the common-sense rules we experience every day, where water pours, syrup sticks and coffee swirls and slows under the effect of viscosity. In these extraordinary fluids, motion often organizes itself into quantized vortices: tiny, long-lived whirlpools that act as the fundamental building blocks of superfluid flow.

• New reactor produces clean energy and carbon nanotubes from natural gas

  Scientists from the University of Cambridge have developed a new reactor that converts natural gas (a common energy source primarily composed of methane) into two highly valuable resources: clean hydrogen fuel and carbon nanotubes, which are ultralight and much stronger than steel.

• Raindrops form 'sandballs' as they roll downhill, contributing more to erosion than previously thought

  What happens as a raindrop impacts bare soil has been fairly well-studied, but what happens to raindrops afterward is poorly understood. We know that the initial splash of raindrops on soil contributes to erosion, but a new study, published in the Proceedings of the National Academy of Sciences, finds that the journey of the raindrop downhill might have an even bigger impact on erosion than the initial splash.

• Promising new superconducting material discovered with the help of AI

  Tohoku University and Fujitsu Limited have successfully used AI to derive new insights into the superconductivity mechanism of a new superconducting material.

• Rare Hall effect reveals design pathways for advanced spintronic materials

  Scientists at Ames National Laboratory, in collaboration with Indranil Das's group at the Saha Institute of Nuclear Physics (India), have found a surprising electronic feature in transitional metal-based compounds that could pave the way for a new class of spintronic materials for computing and memory technologies.

• Why a chiral magnet is a direction-dependent street for electrons

  RIKEN physicists have discovered for the first time why the magnitude of the electron flow depends on direction in a special kind of magnet. This finding could help to realize future low-energy devices.

• How does Santa do it all? Quantum physics, that's how, says scientist

  Every year, Santa Claus races around the globe in a matter of hours to bring presents to children all over the world.

• Anything-goes 'anyons' may be at the root of surprising quantum experiments

  In the past year, two separate experiments in two different materials captured the same confounding scenario: the coexistence of superconductivity and magnetism. Scientists had assumed that these two quantum states are mutually exclusive; the presence of one should inherently destroy the other.

• Kolmogorov-Arnold networks bridge AI and scientific discovery by increasing interpretability

  AI has successfully been applied in many areas of science, advancing technologies like weather prediction and protein folding. However, there have been limitations for the world of scientific discovery involving more curiosity-driven research. But that may soon change, thanks to Kolmogorov-Arnold networks (KANs).

• Who was Amelia Frank? The life of a forgotten physicist

  In 1977, an American physicist named John H. Van Vleck won the Nobel Prize for his work on magnetism. In his Nobel lecture, amid a discussion of rare earth elements, one sentence leaps out:

• AI uncovers double-strangeness: A new double-Lambda hypernucleus

  Researchers from the High Energy Nuclear Physics Laboratory at the RIKEN Pioneering Research Institute (PRI) in Japan and their international collaborators have made a discovery that bridges artificial intelligence and nuclear physics. By applying deep learning techniques to a vast amount of unexamined nuclear emulsion data from the J-PARC E07 experiment, the team identified, for the first time in 25 years, a new double-Lambda hypernucleus.

• Controlling exciton flow in moiré superlattices: New method leverages correlated electrons

  Excitons are pairs of bound negatively charged electrons and positively charged holes that form in semiconductors, enabling the transport of energy in electronic devices. These pairs of charge carriers also emerge in transition metal dichalcogenides, thin semiconducting materials comprised of a transition metal and two chalcogen atoms.

• Quantum entanglement could connect drones for disaster relief, bypassing traditional networks

  Any time you use a device to communicate information—an email, a text message, any data transfer—the information in that transmission crosses the open internet, where it could be intercepted. Such communications are also reliant on internet connectivity, often including wireless signal on either or both ends of a transmission.

• First beta-delayed neutron emission observed in rare fluorine-25 isotope

  A research team at the Facility for Rare Isotope Beams (FRIB) is the first ever to observe a beta-delayed neutron emission from fluorine-25, a rare, unstable nuclide. Using the FRIB Decay Station Initiator (FDSi), the team found contradictions in prior experimental findings. The results led to a new line of inquiry into how particles in exotic, unstable isotopes remain bound under extreme conditions. Led by Robert Grzywacz, professor of physics at the University of Tennessee, Knoxville (UTK), the team included Jack Peltier, undergraduate student at UTK, Zhengyu Xu, postdoctoral researcher at UTK, Sean Liddick, professor of chemistry at FRIB and interim chairperson of MSU's Department of Chemistry, and Rebeka Lubna, scientist at FRIB.

• New 'cloaking device' concept shields electronics from disruptive magnetic fields

  University of Leicester engineers have unveiled a concept for a device designed to magnetically "cloak" sensitive components, making them invisible to detection.

• Measuring how materials hotter than the sun's surface conduct electricity

  Warm dense matter is a state of matter that forms at extreme temperatures and pressures, like those found at the center of most stars and many planets, including Earth. It also plays a role in the generation of Earth's magnetic field and in the process of nuclear fusion.

• Machine learning and microscopy solve 170-year-old mystery of premelting ice

  Through a novel combination of machine learning and atomic force microscopy, researchers in China have unveiled the molecular surface structure of "premelted" ice, resolving a long-standing mystery surrounding the liquid-like layer which forms on icy surfaces.

• A cryogenic winter for tomorrow's accelerator

  Behind every particle collision generated at the Large Hadron Collider is a multitude of technical feats. One of these is refrigeration on an industrial scale. To guide the particles, the thousands of superconducting magnets in the accelerator must be cooled to a temperature of close to absolute zero. This makes the LHC the largest cryogenic installation in the world: 23 of its 27 kilometers are maintained at 1.9 Kelvin (-271°C) using refrigerators in which superfluid helium circulates.

• Why quantum computers have memory problems over time

  A team of Australian and international scientists has, for the first time, created a full picture of how errors unfold over time inside a quantum computer—a breakthrough that could help make future quantum machines far more reliable.

• Private donors pledge $1 billion for world's largest particle accelerator

  Europe's physics lab CERN on Thursday said private donors had pledged $1 billion toward the construction of a new particle accelerator that would be by far the world's biggest.

• Hybrid excitons: Combining the best of both worlds

  Faster, more efficient, and more versatile—these are the expectations for the technology that will produce our energy and handle information in the future. But how can these expectations be met? A major breakthrough in physics has now been made by an international team of researchers from the Universities of Göttingen, Marburg, the Berlin Humboldt in Germany, and Graz in Austria.