Phys.org Physics

• Flat Fermi surface in altermagnets enables quantum limit spin currents

  The key feature of spintronic devices is their ability to use spin currents to transfer momentum, enabling low-energy, high-speed storage and logical signal control. These devices are usually manipulated by electric currents and fields. The charge-to-spin conversion efficiency (CSE) is a key metric for evaluating their performance.

• Silicon atom processor links 11 qubits with more than 99% fidelity

  In order to scale quantum computers, more qubits must be added and interconnected. However, prior attempts to do this have resulted in a loss of connection quality, or fidelity. But, a new study published in Nature details the design of a new kind of processor that overcomes this problem. The processor, developed by the company Silicon Quantum Computing, uses silicon—the main material used in classical computers—along with phosphorus atoms to link 11 qubits.

• Scientists build a quantum computer that can repair itself using recycled atoms

  Like their conventional counterparts, quantum computers can also break down. They can sometimes lose the atoms they manipulate to function, which can stop calculations dead in their tracks. But scientists at the US-based firm Atom Computing have demonstrated a solution that allows a quantum computer to repair itself while it's still running.

• Elegant solution for measuring ultrashort laser pulses discovered

  Ultrashort laser pulses—that are shorter than a millionth of a millionth of a second—have transformed fundamental science, engineering and medicine. Despite this, their ultrashort duration has made them elusive and difficult to measure.

• Super strain-resistant superconductors: Study narrows down the hidden symmetry

  Superconductors are materials that can conduct electricity with zero resistance, usually only at very low temperatures. Most superconductors behave according to well-established rules, but strontium ruthenate, Sr₂RuO₄, has defied clear understanding since its superconducting properties were discovered in 1994. It is considered one of the cleanest and best-studied unconventional superconductors, yet scientists still debate the precise structure and symmetry of the electron pairing that gives rise to its remarkable properties.

• A simple spin swap reveals exotic anyons

  Researchers from the University of Innsbruck, the Collège de France, and the Université Libre de Bruxelles have developed a simple yet powerful method to reveal anyons—exotic quantum particles that are neither bosons nor fermions—in one-dimensional systems. Their paper is published in Physical Review Letters.

• Color-superconducting quark matter may explain stability of massive neutron stars

  Describing matter under extreme conditions, such as those found inside neutron stars, remains an unsolved problem. The density of such matter is equivalent to compressing around 100,000 Eiffel Towers into a single cubic centimeter. In particular, the properties of so-called quark matter—which consists of the universe's fundamental building blocks, the quarks, and may exist in extremely dense regions—play a central role.

• Shortest light pulse ever created captures ultrafast electron dynamics

  Electrons determine everything: how chemical reactions unfold, how materials conduct electricity, how biological molecules transfer energy, and how quantum technologies operate. But electron dynamics happens on attosecond timescales—far too fast for conventional measurement tools.

• 'Ouzo effect' reveals how oil droplets can resist flow and form stable patterns in liquids

  Whether it's Greek ouzo, French pastis or Turkish raki, when these spirits are diluted with water, the mixture becomes cloudy. The reason for this is that the aniseed oils contained in the spirit dissolve well in alcohol but not in water. The clear ouzo from the bottle has a high alcohol content at which the oil is fully soluble.

• Conventional entanglement can have thousands of hidden topologies in high dimensions

  Researchers from the University of the Witwatersrand in South Africa, in collaboration with Huzhou University, discovered that the entanglement workhorse of most quantum optics laboratories can have hidden topologies, reporting the highest ever observed in any system: 48 dimensions with over 17,000 topological signatures, an enormous alphabet for encoding robust quantum information.

• How cricket balls move: The science behind swing, seam and spin

  If you've ever watched a batter get beaten by a ball that curved, jagged or dipped at the last moment, you've seen one of cricket's great mysteries.

• Subsystem resetting: Researchers discover a new route to control phase transitions in complex systems

  Researchers in the Department of Theoretical Physics at Tata Institute of Fundamental Research (TIFR), Mumbai, have discovered that instead of manipulating every component or modifying interactions in a many-body system, occasionally resetting just a small fraction can reshape how the entire system behaves, including how it transitions from one phase to another.

• A 3D-printed Christmas tree made entirely of ice

  A team of physicists from the University of Amsterdam's Institute of Physics has 3D-printed a Christmas tree made entirely of ice. Researchers Menno Demmenie, Stefan Kooij and Daniel Bonn used no freezing technology or refrigeration equipment—just water and a vacuum. In time-lapse videos, you can see how the Christmas tree is printed and how it melts again when the vacuum pump is turned off. The work is published on the arXiv preprint server.

• Subtle twist in materials prompts surprising electromagnetic behavior

  Materials react differently to electric and magnetic fields, and these reactions are known as electromagnetic responses. In many solid materials, unusual electromagnetic responses have been known to only emerge when specific symmetries are broken.

• Active thermal metasurfaces amplify heat signatures by a factor of nine

  Light undergoes a unique phenomenon called superscattering, an optical illusion where a very small object scatters far more light than expected. This happens when multiple scattering modes overlap and interact, allowing tiny objects to scatter far more light than their size should allow.

• Physicists push superconducting diodes to high temperatures

  For the first time, researchers in China have demonstrated a high-temperature superconducting diode effect, which allows a supercurrent to flow in both directions. Published in Nature Physics, the team's result could help address the noisy signals that pose a fundamental challenge in quantum computing.

• Embrace chaos to get lifelike movement from synthetic materials, researchers say

  When people think of high-powered machines, they'd likely think of muscle cars before their own muscles. But muscles and other living tissues can do energetic things very quickly—they twitch, snap and beat—which is how physics defines power.

• Laser light and the quantum nature of gravity: Proposed experiment could measure graviton energy exchange

  When two black holes merge or two neutron stars collide, gravitational waves can be generated. They spread at the speed of light and cause tiny distortions in space-time. Albert Einstein predicted their existence, and the first direct experimental observation dates from 2015.

• Altermagnetism in RuO₂ thin films: A new magnetic material for the AI era

  A research team has demonstrated that thin films of ruthenium dioxide (RuO₂) exhibit altermagnetism—the defining property of what is now recognized as the third fundamental class of magnetic materials.

• Shaking magnets with ultrafast light pulses reveals surprising spin control

  An international team of researchers led by Lancaster University has discovered a highly efficient mechanism for shaking magnets using very short light pulses, shorter than a trillionth of a second. Their research is published in Physical Review Letters.

• A universal law could explain how large trades change stock prices

  Financial markets are often seen as chaotic and unpredictable. Every day, traders around the world buy shares and sell assets in a whirlwind of activity. It looks like a system of total randomness—but is it really?

• The hidden physics of knot formation in fluids

  Knots are everywhere—from tangled headphones to DNA strands packed inside viruses—but how an isolated filament can knot itself without collisions or external agitation has remained a longstanding puzzle in soft-matter physics.

• Integrative quantum chemistry method unlocks secrets of advanced materials

  A new computational approach developed at the University of Chicago promises to shed light on some of the world's most puzzling materials—from high-temperature superconductors to solar cell semiconductors—by uniting two long-divided scientific perspectives.

• Near-infrared light enables wireless power and data transfer for medical implants

  A new study from a research team at the Center for Wireless Communications Network and Systems (CWC-NS) at the University of Oulu has introduced an approach using near-infrared (NIR) light beyond light therapy to facilitate simultaneous wireless power transfer and communication to electronic implantable medical devices (IMDs). Previously, the research team demonstrated that NIR light for wireless communication is feasible, and now the team made progress by involving wireless charging capabilities using the same light.

• Scientists create stable, switchable vortex knots inside liquid crystals

  The knots in your shoelaces are familiar, but can you imagine knots made from light, water, or from the structured fluids that make LCD screens shine?