Phys.org Physics News Feeds

  • Decades of research bring quantum dots to brink of widespread use
    on August 5, 2021 at 8:01 pm

    A new article in Science magazine gives an overview of almost three decades of research into colloidal quantum dots, assesses the technological progress for these nanometer-sized specs of semiconductor matter, and weighs the remaining challenges on the path to widespread commercialization for this promising technology with applications in everything from TVs to highly efficient sunlight collectors.

  • This quantum crystal could be a new dark matter sensor
    on August 5, 2021 at 6:00 pm

    Physicists at the National Institute of Standards and Technology (NIST) have linked together, or “entangled,” the mechanical motion and electronic properties of a tiny blue crystal, giving it a quantum edge in measuring electric fields with record sensitivity that may enhance understanding of the universe.

  • A major challenge to harvesting fusion energy on Earth
    on August 5, 2021 at 4:35 pm

    A key challenge for scientists striving to produce on Earth the fusion energy that powers the sun and stars is preventing what are called runaway electrons, particles unleashed in disrupted fusion experiments that can bore holes in tokamaks, the doughnut-shaped machines that house the experiments. Scientists led by researchers at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have used a novel diagnostic with wide-ranging capabilities to detect the birth, and the linear and exponential growth phases of high-energy runaway electrons, which may allow researchers to determine how to prevent the electrons’ damage.

  • Joining topological insulators with magnetic materials for energy-efficient electronics
    on August 5, 2021 at 1:47 pm

    A new Monash review throws the spotlight on recent research in heterostructures of topological insulators and magnetic materials.

  • New approach to information transfer reaches quantum speed limit
    on August 5, 2021 at 11:19 am

    Even though quantum computers are a young technology and aren’t yet ready for routine practical use, researchers have already been investigating the theoretical constraints that will bound quantum technologies. One of the things researchers have discovered is that there are limits to how quickly quantum information can race across any quantum device.

  • Researchers around the world are buzzing about a candidate superconductor
    on August 4, 2021 at 7:38 pm

    Since receiving a $25 million grant in 2019 to become the first National Science Foundation (NSF) Quantum Foundry, UC Santa Barbara researchers affiliated with the foundry have been working to develop materials that can enable quantum information-based technologies for such applications as quantum computing, communications, sensing, and simulation.

  • Manipulating magnetic domain dynamics in ultrathin multi-layered materials
    on August 4, 2021 at 3:58 pm

    A novel route to tune and control the magnetic domain wall motions employing combinations of useful magnetic effects inside very thin film materials, has been demonstrated by researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST) in Korea. The research, published in the journal Advance Science, offers a new insights into spintronics and a step towards new ultrafast, ultrasmall, and power-efficient IT devices.

  • When vibrations increase on cooling: Anti-freezing observed
    on August 4, 2021 at 3:54 pm

    An international team has observed an amazing phenomenon in a nickel oxide material during cooling: Instead of freezing, certain fluctuations actually increase as the temperature drops. Nickel oxide is a model system that is structurally similar to high-temperature superconductors. The experiment shows once again that the behavior of this class of materials still holds surprises.

  • Exotic property of ‘ambidextrous’ crystals points to new magnetic phenomena
    on August 4, 2021 at 1:37 pm

    Researchers from Skoltech, KTH Royal Institute of Technology, and Uppsala University have predicted the existence of antichiral ferromagnetism, a nontrivial property of some magnetic crystals that opens the door to a variety of new magnetic phenomena. The paper was published in the journal Physical Review B.

  • Rate of nuclear reaction in exploding stars
    on August 4, 2021 at 1:31 pm

    New research by Surrey’s Nuclear Physics Group has shown that it’s possible to mimic excited quantum states with exotic nuclei, opening up a host of opportunities for next generation radioactive beam facilities, such as the Facility for Rare Isotope Beams (FRIB).

  • LEDs light the way to coronavirus disinfection
    on August 4, 2021 at 1:00 pm

    LEDs are commonly used for sterilization—you may be using one to clean your electric toothbrush, for example. In the continued effort to combat the coronavirus pandemic, LEDs can also help inactivate SARS-CoV-2.

  • Indoor lighting creates power for rechargeable devices, sensors
    on August 4, 2021 at 1:00 pm

    As more of our devices require recharging of their batteries, researchers are looking to ambient lighting as a potential source of generating small amounts of power for indoor devices.

  • Bringing discoveries to light: X-ray science at Argonne
    on August 3, 2021 at 6:44 pm

    For more than 25 years, the Advanced Photon Source’s intense X-rays have enabled important breakthroughs. With a massive upgrade in the works, scientists will be able to see things at scale never seen before.

  • Built-in vibration control may help soundproof spaces
    on August 3, 2021 at 5:22 pm

    A different kind of design for absorbing vibrations could help better soundproof walls and make vehicles more streamlined, a new study shows.

  • Acquisition of channel state information for mmWave MIMO: Traditional and machine learning approaches
    on August 3, 2021 at 3:44 pm

    Millimeter wave (mmWave) communications have attracted extensive interest from academia, industry, and government as they can make full use of abundant frequency resources at the high-frequency band to achieve ultra-high-speed data transmission. The mmWave communication systems are usually equipped with large antenna arrays, known as mmWave massive multiple-input multiple-output (MIMO), to generate highly directional beams and compensate for the severe path loss in the high frequency band. However, the performance of directional beamforming largely relies on the accuracy of channel state information (CSI) acquisition. Compared to the traditional MIMO systems, the CSI acquisition in mmWave massive MIMO systems is challenging. On one hand, the large antenna arrays form a high dimension channel matrix, whose estimation consumes more resources, e.g., pilot sequence overhead, sounding beam overhead, and computational complexity. On the other hand, the mmWave massive MIMO typically employs a hybrid beamforming architecture, where the radio frequency (RF) chains are much fewer than the antennas. Therefore, we can only obtain a low-dimension signal from the RF chains instead of directly getting a high-dimension signal from the frontend antennas, which makes CSI acquisition much more challenging than usual.

  • Artificial stomach reveals fluid dynamics of food digestion
    on August 3, 2021 at 3:00 pm

    In efforts to fight obesity and enhance drug absorption, scientists have extensively studied how gastric juices in the stomach break down ingested food and other substances. However, less is known about how the complex flow patterns and mechanical stresses produced in the stomach contribute to digestion.

  • Mott insulator exhibits a sharp response to electron injection
    on August 3, 2021 at 2:02 pm

    In a finding that will give theorists plenty to ponder, an all-RIKEN team has observed an unexpected response in an exotic material known as a Mott insulator when they injected electrons into it. This observation promises to give physicists new insights into such materials, which are closely related to high-temperature superconductors.

  • New viable means of storing information for quantum technologies?
    on August 3, 2021 at 1:41 pm

    Quantum information could be behind the next technological revolution. By analogy with the bit in classical computing, the qubit is the basic element of quantum computing. However, demonstrating the existence of this information storage unit and using it remains complex, and hence limited. In a study published on 3 August 2021 in Physical Review X, an international research team consisting of CNRS researcher Fabio Pistolesi1 and two foreign researchers used theoretical calculations to show that it is possible to realize a new type of qubit, in which information is stored in the oscillation amplitude of a carbon nanotube.

  • Running quantum software on a classical computer
    on August 3, 2021 at 12:08 pm

    Two physicists, from EPFL and Columbia University, have introduced an approach for simulating the quantum approximate optimization algorithm using a traditional computer. Instead of running the algorithm on advanced quantum processors, the new approach uses a classical machine-learning algorithm that closely mimics the behavior of near-term quantum computers.

  • Finding the cause of a fatal problem in rocket engine combustors
    on August 2, 2021 at 7:23 pm

    Rocket engines contain confined combustion systems, which are essentially combustion chambers. In these chambers, nonlinear interactions among turbulent fuel and oxidizer flows, sound waves, and heat produced from chemical reactions cause an unstable phenomenon called “combustion oscillations.” The force of these oscillations on the body of the combustion chamber—the mechanical stress on the chamber— is high enough to threaten catastrophic failure of the engine. What causes these oscillations? The answer remains to be found.

  • Ultrafast X-ray provides new look at plasma discharge breakdown in water
    on July 30, 2021 at 4:51 pm

    Occurring faster than the speed of sound, the mystery behind the breakdown of plasma discharges in water is one step closer to being understood as researchers pursue applying new diagnostic processes using state-of-the-art X-ray imaging to the challenging subject.

  • Electron microscopy in the age of automation
    on July 30, 2021 at 4:31 pm

    “Many of the greatest challenges of our time, from clean energy to environmental justice, require new approaches to the craft of scientific experimentation. This is exceedingly apparent in the field of electron microscopy. As researchers utilize this powerful window to peer into the atomic machinery behind today’s technologies, they are increasingly inundated with data and constrained by traditional operating models. We must leverage artificial intelligence and machine learning in our scientific instruments if we are to unlock breakthrough discoveries.”

  • Natural mineral hackmanite enables new method of x-ray imaging
    on July 30, 2021 at 2:41 pm

    Researchers from the University of Turku have discovered a new method of X-ray imaging based on the coloring abilities of the natural mineral hackmanite. The international group of researchers also found out how and why hackmanite changes color upon exposure to X-rays.

  • Ultracold transistors serve as their own memory devices
    on July 30, 2021 at 11:59 am

    Digital transistors—assembled by the billions in today’s computer chips—act as near-perfect electronic switches. In the “on” position, achieved when an above-threshold voltage is applied to the device, the transistor allows current to flow. When the switch is off, the transistor prevents the flow of current. The on/off positions of the switch translate into the 1s and 0s of digital computation.

  • Searching for dark matter inside the Earth
    on July 30, 2021 at 11:57 am

    Dark matter remains one of the greatest mysteries in science. Despite decades of astronomical evidence for its existence, no one has yet been able to find any sign of it closer to home. There have been dozens of efforts to do so, and one of the most prominent just hit a milestone—the release and analysis of eight years of data. The IceCube Neutrino Observatory will soon be releasing results from those eight years, but for now let’s dive in to what exactly they are looking for.

  • Engineers bend light to enhance wavelength conversion
    on July 30, 2021 at 9:00 am

    Electrical engineers from the UCLA Samueli School of Engineering have developed a more efficient way of converting light from one wavelength to another, opening the door for improvements in the performance of imaging, sensing and communication systems.

  • Researchers propose a method of magnetizing a material without applying an external magnetic field
    on July 29, 2021 at 8:00 pm

    Magnetizing a material without applying an external magnetic field is proposed by researchers at São Paulo State University (UNESP), Brazil, in an article published in the journal Scientific Reports, where they detail the experimental approach used to achieve this goal.

  • Researchers kick-start magnetic spin waves at nanoscale in pursuit of low energy computing
    on July 29, 2021 at 5:53 pm

    An international team from Delft, Lancaster, Nijmegen, Kiev and Salerno has demonstrated a new technique to generate magnetic waves that propagate through the material at a speed much faster than the speed of sound.

  • A new information storage and processing device
    on July 29, 2021 at 4:59 pm

    A team of scientists has developed a means to create a new type of memory, marking a notable breakthrough in the increasingly sophisticated field of artificial intelligence. 

  • AI learns physics to optimize particle accelerator performance
    on July 29, 2021 at 3:39 pm

    Machine learning, a form of artificial intelligence, vastly speeds up computational tasks and enables new technology in areas as broad as speech and image recognition, self-driving cars, stock market trading and medical diagnosis.