Phys.org Physics

• Quantum effect could power the next generation of battery-free devices

  A new study has revealed how tiny imperfections and vibrations inside a promising quantum material could be used to control an unusual quantum effect, opening new possibilities for smaller, faster, and more efficient energy-harvesting devices.

• When light 'thinks' like the brain: The connection between photons and artificial memory

  An international study has revealed a surprising connection between quantum physics and the theoretical models underlying artificial intelligence. The study results from a collaboration between the Institute of Nanotechnology of the National Research Council (Cnr-Nanotec), the Italian Institute of Technology (IIT), and Sapienza University of Rome, together with international research institutions. The research paper was published recently in the journal Physical Review Letters.

• Physicists watch light drift in quantized steps for the first time

  In physics, the classical "Hall effect," discovered in the late 19th century, describes how a transverse voltage is generated when an electric current is exposed to a perpendicular magnetic field. Simply put, the magnetic field causes the electrons, which are negatively charged, to drift sideways, creating a negative charge on one edge of the conducting strip and a positive charge on the opposite side.

• AI develops easily understandable solutions for unusual experiments in quantum physics

  Researchers at the University of Tuebingen, working with an international team, have developed an artificial intelligence that designs entirely new, sometimes unusual, experiments in quantum physics and presents them in a way that is easily understandable for researchers. This includes experimental setups that humans might never have considered. The new AI doesn't just create a single design proposal; instead, it writes computer code that generates a whole series of physical experiments, that is, groups of experiments with similar outputs. The study has been published in the journal Nature Machine Intelligence.

• Clearing the path for turbulence-free quantum communication

  A University of Ottawa team has developed a new way to protect free-space quantum key distribution (QKD) from atmospheric turbulence, one of the main causes of distortion and errors when sending quantum information through air. Their paper, "All-optical turbulence mitigation for free-space quantum key distribution using stimulated parametric down-conversion," appears in the journal Optica.

• Electrical control of magnetism in 2D materials promises to advance spintronics

  Conventional electronics process information leveraging the electrical charge of electrons. Over the past few decades, some electronics engineers have been exploring the potential of a different type of device that instead processes and stores data exploiting the intrinsic magnetic moment (i.e., spin) of electrons.

• Hair-width LEDs could eventually replace lasers

  LEDs no wider than a human hair could soon take on work traditionally handled by lasers, from moving data inside server racks to powering next-generation displays. New research co-authored by UC Santa Barbara doctoral student Roark Chao points to a practical path forward. The study is published in the journal Optics Express.

• Alloy-engineered valleytronics: Microscopic mechanism gives scientists precise control over how excitons behave

  Scientists have observed a new microscopic mechanism enabling precise control of the magneto-optical properties of excitons in alloys of two-dimensional semiconductors. This discovery opens up tangible prospects for technological applications in devices exploiting valleytronics. The research findings were published in the journal Physical Review Letters.

• Diamond owl swoops in with new method to keep electronics cool

  At Rice University, a research lab's signature keepsake has helped perfect a method for growing patterned diamond surfaces that could help decrease operating temperatures in electronics by 23 degrees Celsius. The paper is published in the journal Applied Physics Letters.

• Twisting optical fiber creates a robust new pathway for light

  Light powers everything from communications to sensing, yet even tiny imperfections can scatter it and weaken signals. To address this, a team led by the University of Bath—working with the University of Cambridge and international partners—has developed a new structure that keeps light flowing smoothly even through bends, twists or damage, with the potential to operate over unprecedented distances.

• Quantum computers go high-dimensional with a four-state photon gate

  The collaboration of TU Wien with research groups in China has resulted in a crucial building block for a new kind of quantum computer: The realization of a novel type of quantum logic gate makes it possible to carry out quantum computations on pairs of photons that are each in four different quantum states, or combinations thereof. The advancement is an important milestone for optical quantum computers. The study has now been published in Nature Photonics.

• Ultra-efficient optical sensors can keep light circulating longer inside a microscopic chip

  CU Boulder researchers have built high-performing optical microresonators, opening the door for new sensor technologies. At its simplest form, a microresonator is a tiny device that can trap light and build up its intensity. Once the intensity is high enough, researchers can perform unique light operations.

• Quantum algorithm beats classical tools on complement sampling tasks

  Quantum computers—devices that process information using quantum mechanical effects—have long been expected to outperform classical systems on certain tasks. Over the past few decades, researchers have worked to rigorously demonstrate such advantages, ideally in ways that are provable, verifiable and experimentally realizable.

• How to improve the performance of qubits: Super-fast fluctuation detection achieved

  Using commercially available technology and innovative methods, researchers at NBI have pushed the limits of how fast you can detect changes in the sensitive quantum states in the qubit. Their work allows researchers to follow rapid changes in qubit performance that were previously invisible. The study is published in the journal Physical Review X.

• Sunray-like ripples emerge on a frozen reaction front

  Researchers in Belgium have unveiled a striking chemical reaction in which ripples along a frozen reaction front resemble the rays of a shining star. Publishing their results in Physical Review Letters, Anne De Wit and colleagues at the Université Libre de Bruxelles have shed new light on the patterns that emerge in reaction–diffusion systems, offering fresh insight into how similar structures arise in the natural world.

• Quantum reservoir computing peaks at the edge of many-body chaos, study suggests

  Reservoir computing is a promising machine learning-based approach for the analysis of data that changes over time, such as weather patterns, recorded speech or stock market trends. Classical reservoir computing techniques are known to perform best at the "edge of chaos," or in simpler terms, at a "sweet spot" in which the behavior of systems is neither entirely predictable (i.e., order) nor completely unpredictable (i.e., chaos).

• Metamaterial image sensor keeps colors clear even under oblique light

  Smartphone cameras are becoming smaller, yet photos are becoming sharper. Korean researchers have elevated the limits of next-generation smartphone cameras by developing a new image sensor technology that can accurately represent colors regardless of the angle at which light enters. The team achieved this by utilizing a "metamaterial" that designs the movement of light through structures too small to be seen with the naked eye.

• Living tissues are shaped by self-propelled topological defects, biophysicists find

  With a new mathematical model, a team of biophysicists has revealed fresh insights into how biological tissues are shaped by the active motion of structural imperfections known as "topological defects." Published in Physical Review Letters, the results build on our latest understanding of tissue formation and could even help resolve long-standing experimental mysteries surrounding our own organs.

• Neutron scattering helps clarify magnetic behavior in altermagnetic material

  Scientists at the U.S. Naval Research Laboratory (NRL) have identified the true source of a magnetic effect seen in the material ruthenium dioxide (RuO₂), helping resolve an active debate in the rapidly growing field of altermagnetism. The study is published in the journal ACS Applied Materials & Interfaces.

• Can a chatbot be a co-author? AI helps crack a long-stalled gluon amplitude proof

  Like many scientists, theoretical physicist Andrew Strominger was unimpressed with early attempts at probing ChatGPT, receiving clever-sounding answers that didn't stand up to scrutiny. So he was skeptical when a talented former graduate student paused a promising academic career to take a job with OpenAI. Strominger told him physics needed him more than Silicon Valley.

• Quantum trembling: Why there are no truly flat molecules

  Traditional chemistry textbooks present a tidy picture: Atoms in molecules occupy fixed positions, connected by rigid rods. A molecule such as formic acid (methanoic acid, HCOOH) is imagined as two-dimensional—flat as a sheet of paper. But quantum physics tells a different story. In reality, nature resists rigidity and forces even the simplest structures into the third dimension.

• Phonon lasers unlock ultrabroadband acoustic frequency combs

  Acoustic frequency combs organize sound or mechanical vibrations into a series of evenly spaced frequencies, much like the teeth on a comb. They are the acoustic counterparts of optical frequency combs, which consist of equally spaced spectral lines and act as extraordinarily precise rulers for measuring light.

• Quantum entanglement could link distant telescopes for sharper images

  To capture higher-definition and sharper images of cosmological objects, astronomers sometimes combine the data collected by several telescopes. This approach, known as long-baseline interferometry, entails comparing the light signals originating from distant objects and picked up by different telescopes that are at different locations, then reconstructing images using computational techniques.

• Is this glass square the long, long future of data storage?

  Scientists at Microsoft Research in the United States have demonstrated a system called Silica for writing and reading information in ordinary pieces of glass which can store two million books' worth of data in a thin, palm-sized square.

• Terahertz spectroscopy finds nitrogen can lengthen GaAs-like LO phonon decay

  An Osaka Metropolitan University-led research team investigated the decay time of coherent longitudinal optical (LO) phonons both in a GaAs1−xNx epilayer and in a GaAs single crystal to clarify the effects of dilute nitridation.