Phys.org Physics

• AI captures particle accelerator behavior to optimize machine performance

  Keeping high-power particle accelerators at peak performance requires advanced and precise control systems. For example, the primary research machine at the U.S. Department of Energy's Thomas Jefferson National Accelerator Facility features hundreds of fine-tuned components that accelerate electrons to 99.999% the speed of light.

• The shape of skis makes the biggest difference in maneuverability

  From the biathlon to the slopestyle to the giant slalom, raising a ski above your head after crossing the finish line is the triumphant Olympic skier's standard celebration. But why do the skis of the competitors in each event look so different?

• Cutting down on quantum-dot crosstalk: Precise measurements expose a new challenge

  Devices that can confine individual electrons are potential building blocks for quantum information systems. But the electrons must be protected from external disturbances. RIKEN researchers have now shown how quantum information encoded into a so-called quantum dot can be negatively affected by nearby quantum dots. This has implications for developing quantum information devices based on quantum dots.

• Physicists develop new protocol for building photonic graph states

  Physicists have long recognized the value of photonic graph states in quantum information processing. However, the difficulty of making these graph states has left this value largely untapped. In a step forward for the field, researchers from The Grainger College of Engineering at the University of Illinois Urbana-Champaign have proposed a new scheme they term "emit-then-add" for producing highly entangled states of many photons that can work with current hardware. Published in npj Quantum Information, their strategy lays the groundwork for a wide range of quantum enhanced operations including measurement-based quantum computing.

• Silicon metasurfaces boost optical image processing with passive intensity-based filtering

  Of the many feats achieved by artificial intelligence (AI), the ability to process images quickly and accurately has had an especially impressive impact on science and technology. Now, researchers in the McKelvey School of Engineering at Washington University in St. Louis have found a way to improve the efficiency and capability of machine vision and AI diagnostics using optical systems instead of traditional digital algorithms.

• Photonic integrated circuits enable programmable non-Abelian 'braiding' of light states

  A research team has successfully implemented a programmable spinor lattice on a photonic integrated circuit (PIC). This platform enables the realization of non-Abelian physics, in which the outcome of operations depends on their sequence, within an integrated photonic system.

• Nanolaser on a chip could cut computer energy use in half

  Researchers at DTU have developed a nanolaser that could be the key to much faster and much more energy-efficient computers, phones, and data centers. The technology offers the prospect of thousands of the new lasers being placed on a single microchip, thus opening a digital future where data is no longer transmitted using electrical signals, but using light particles, photons. The invention has been published in the journal Science Advances.

• A new turbulence equation for eddy interactions: AI and physics team up to tackle notoriously difficult question

  The currents of the oceans, the roiling surface of the sun, and the clouds of smoke billowing off a forest fire—all are governed by the same laws of physics and give rise to a complex phenomenon known as turbulence. But precisely modeling this chaotic motion of fluids, encompassing many scales of time and space, has remained out of reach of scientists for more than a century.

• Rolling out the carpet for spin qubits with new chip architecture

  Researchers at QuTech in Delft, The Netherlands, have developed a new chip architecture that could make it easier to test and scale up quantum processors based on semiconductor spin qubits. The platform, called QARPET (Qubit-Array Research Platform for Engineering and Testing) and reported in Nature Electronics, allows hundreds of qubits to be characterized within the same test-chip under the same operating conditions used in quantum computing experiments.

• Rocket science? 3D printing soft matter in zero gravity

  What happens to soft matter when gravity disappears? To answer this, UvA physicists launched a fluid dynamics experiment on a sounding rocket. The suborbital rocket reached an altitude of 267 km before falling back to Earth, providing six minutes of weightlessness.

• AI method accelerates liquid simulations by learning fundamental physical relationships

  Researchers at the University of Bayreuth have developed a method using artificial intelligence that can significantly speed up the calculation of liquid properties. The AI approach predicts the chemical potential—an indispensable quantity for describing liquids in thermodynamic equilibrium. The researchers present their findings in a new study published in Physical Review Letters.

• A familiar magnet gets stranger: Why cobalt's topological states could matter for spintronics

  The element cobalt is considered a typical ferromagnet with no further secrets. However, an international team led by HZB researcher Dr. Jaime Sánchez-Barriga has now uncovered complex topological features in its electronic structure. Spin-resolved measurements of the band structure (spin-ARPES) at BESSY II revealed entangled energy bands that cross each other along extended paths in specific crystallographic directions, even at room temperature. As a result, cobalt can be considered as a highly tunable and unexpectedly rich topological platform, opening new perspectives for exploiting magnetic topological states in future information technologies.

• Parabolic mirror-enhanced Raman spectroscopy enables high-sensitivity trace gas detection

  A research team led by Prof. Fang Yonghua from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences proposed and systematically optimized a novel parabolic mirror cavity-enhanced Raman spectroscopy (PMCERS) technique, achieving a marked improvement in gas detection sensitivity through the integration of advanced optical design and signal processing methods. These results were published in Optics & Laser Technology.

• Majorana qubits become readable as quantum capacitance detects even-odd states

  The race to build reliable quantum computers is fraught with obstacles, and one of the most difficult to overcome is related to the promising but elusive Majorana qubits. Now, an international team has read the information stored in these quantum bits. The findings are published in the journal Nature.

• The origin of magic numbers: Why some atomic nuclei are unusually stable

  For the first time, physicists have developed a model that explains the origins of unusually stable magic nuclei based directly on the interactions between their protons and neutrons. Published in Physical Review Letters, the research could help scientists better understand the exotic properties of heavy atomic nuclei and the fundamental forces that hold them together.

• NOvA maps neutrino oscillations over 500 miles with 10 years of data

  Neutrinos are very small, neutral subatomic particles that rarely interact with ordinary matter and are thus sometimes referred to as ghost particles. There are three known types (i.e., flavors) of neutrinos, dubbed muon, electron and tau neutrinos.

• Anomalous magnetoresistance emerges in antiferromagnetic kagome semimetal

  Researchers from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences (CAS), in collaboration with researchers from the Institute of Semiconductors of CAS, revealed anomalous oscillatory magnetoresistance in an antiferromagnetic kagome semimetal heterostructure and directly identified its corresponding topological magnetic structures. The results are published in Advanced Functional Materials.

• Five ways quantum technology could shape everyday life

  The unveiling by IBM of two new quantum supercomputers and Denmark's plans to develop "the world's most powerful commercial quantum computer" mark just two of the latest developments in quantum technology's increasingly rapid transition from experimental breakthroughs to practical applications.

• How charges invert a long-standing empirical law in glass physics

  If you've ever watched a glass blower at work, you've seen a material behaving in a very special way. As it cools, the viscosity of molten glass increases steadily but gradually, allowing it to be shaped without a mold. Physicists call this behavior a strong glass transition, and silica glass is the textbook example. Most polymer glasses behave very differently, and are known as fragile glass formers. Their viscosity rises much more steeply as temperature drops, and therefore they cannot be processed without a mold or very precise temperature control.

• Current flows without heat loss in newly engineered fractional quantum material

  A team of US researchers has unveiled a device that can conduct electricity along its fractionally charged edges without losing energy to heat. Described in Nature Physics, the work, led by Xiaodong Xu at the University of Washington, marks the first demonstration of a "dissipationless fractional Chern insulator," a long-sought state of matter with promising implications for future quantum technologies.

• When heat flows backwards: A neat solution for hydrodynamic heat transport

  When we think about heat traveling through a material, we typically picture diffusive transport, a process that transfers heat from high-temperature to low-temperature as particles and molecules bump into each other, losing kinetic energy in the process. But in some materials, heat can travel in a different way, flowing like water in a pipeline that—at least in principle—can be forced to move in a direction of choice. This second regime is called hydrodynamic heat transport.

• Machine learning reveals hidden landscape of robust information storage

  In a new study published in Physical Review Letters, researchers used machine learning to discover multiple new classes of two-dimensional memories, systems that can reliably store information despite constant environmental noise. The findings indicate that robust information storage is considerably richer than previously understood.

• Could electronic beams in the ionosphere remove space junk?

  A possible alternative to active debris removal (ADR) by laser is ablative propulsion by a remotely transmitted electron beam (e-beam). The e-beam ablation has been widely used in industries, and it might provide higher overall energy efficiency of an ADR system and a higher momentum-coupling coefficient than laser ablation. However, transmitting an e-beam efficiently through the ionosphere plasma over a long distance (10 m–100 km) and focusing it to enhance its intensity above the ablation threshold of debris materials are new technical challenges that require novel methods of external actions to support the beam transmission.

• Laser‑written glass chip pushes quantum communication toward practical deployment

  As quantum computers continue to advance, many of today's encryption systems face the risk of becoming obsolete. A powerful alternative—quantum cryptography—offers security based on the laws of physics instead of computational difficulty. But to turn quantum communication into a practical technology, researchers need compact and reliable devices that can decode fragile quantum states carried by light.

• Supercomputer simulations test turbulence theories at record 35 trillion grid points

  Using the Frontier supercomputer at the Department of Energy's Oak Ridge National Laboratory, researchers from the Georgia Institute of Technology have performed the largest direct numerical simulation (DNS) of turbulence in three dimensions, attaining a record resolution of 35 trillion grid points. Tackling such a complex problem required the exascale (1 billion billion or more calculations per second) capabilities of Frontier, the world's most powerful supercomputer for open science.