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Tritium-infused graphene could sharpen the hunt for neutrino mass

While neutrinos are some of the most abundant particles in the universe, they remain among the least understood. One of the biggest puzzles is their mass: although experiments have shown that neutrinos must have some mass, pinning down exactly how much has proven extraordinarily difficult.

Now, a team of physicists led by Valentina Tozzini of the Institute of Nanoscience in Pisa have published new theoretical calculations in Physical Review C, suggesting that tritium-infused graphene could give future experiments a decisive edge in measuring neutrino masses with unprecedented precision.

New chip offers way to make use of quantum system ‘imperfections’

Quantum technologies promise powerful new kinds of computers, giving scientists new tools to mimic and explore nature at its tiniest scales. At those levels, everything in nature—from atoms and electrons to light itself—follows the strange rules of quantum mechanics. But the real world is never perfectly clean: Signals fade, energy leaks away and systems pick up noise from their surroundings.

“Understanding how quantum systems behave under this messiness is crucial if we want our experiments to say something about nature as it really is, not just idealized setups,” says Govind Krishna, Ph.D. student at KTH Royal Institute of Technology.

Overlooked ‘history force’ may skew particle motion by up to 60% in shaken fluids

Physicists at the University of Bayreuth have investigated the so-called Basset–Boussinesq history force acting on particles in fluids. Due to the difficulty of calculating it, this force is often neglected—a fact that Bayreuth doctoral researcher Frederik Gareis already identified as a secondary school pupil during a student research project with his supervisor. The researchers report their new findings on the history force in Physical Review Fluids.

When particles move in liquids or air with velocities that change over time, several forces act on them, including the often overlooked history force. It arises from the formation of vortices around accelerating particles in fluids. In this way, the surrounding fluid “remembers” previous particle motions and influences their subsequent movement.

“The history force is often ignored because it is mathematically complex and makes calculations significantly more demanding. It is frequently unclear whether neglecting it leads to larger errors in modeling particle motion in fluids,” says Frederik Gareis, a doctoral researcher at the Theoretical Physics I research group at the University of Bayreuth and first author of the study.

Beyond 0 and 1: Ferrotoroidic material can store four magnetic states

Today’s computers store information using only two values: 0 and 1. But as electronic devices become smaller and reach their limits, scientists are searching for new ways to pack more information into the same space. One idea is to use magnetism. In some materials, atoms behave like tiny magnets that can arrange themselves in different patterns. If each pattern represents a different value, one memory element could store more than just two possibilities.

In a study recently published in Nature Communications, researchers have found a material in which these atomic magnets can form four different magnetic states. They showed that these states can be controlled using electric and magnetic fields and remain stable once created.

Using neutron experiments at the Institut Laue-Langevin, the scientists were able to observe each of the four magnetic states that were created by applying electric and magnetic fields. This discovery hints at a future where computers might store significantly more information than today’s binary technologies.

A success for the launch of the Smile satellite to study how the Earth’s magnetosphere responds to the solar wind

A few hours ago, the Smile satellite was launched from the Kourou Spaceport in French Guiana atop a Vega-C rocket. After about 56 minutes, the Smile satellite separated from the rocket’s last stage and began maneuvers that are scheduled to last approximately 25 days. Eleven burns of the spacecraft’s engines will lengthen its orbit, initially circular at an altitude of approximately 700 kilometers, to approximately 121,000 kilometers above the North Pole and approximately 5,000 kilometers above the South Pole.

The Smile (Solar Wind Magnetosphere Ionosphere Link Explorer) mission is a joint project between ESA and the Chinese Academy of Sciences, and is part of ESA’s Cosmic Vision program, which aims to improve our understanding of the solar system. In this case, the focus is on the solar wind and how Earth responds to it. Geomagnetic storms and auroras show, in sometimes spectacular ways, the effects of charged particles from the Sun on the Earth’s magnetosphere.

The Smile satellite is equipped with four instruments designed to study the effects of the solar wind in various ways. It’s not the first mission designed to study the magnetosphere and its interactions with the solar wind, and each new satellite offers new insights. The Smile mission is the first to focus on the mechanisms that lead to the transfer of energy from the solar wind to the Earth’s atmosphere to observe them fully on a global scale.

Prototype sets record for optical quantum information technology

Chinese scientists have developed a programmable quantum computing prototype called Jiuzhang 4.0 that has set a new world record for optical quantum information technology, according to a study published May 13 in the journal Nature.

Led by the University of Science and Technology of China (USTC), the team used the prototype to solve the Gaussian boson sampling problem at a speed more than 1054 times that of the world’s most powerful supercomputer, the study said.

The researchers said they manipulated and detected quantum states of up to 3,050 photons —a significant leap from the 255 photons achieved with the previous Jiuzhang 3.0.

The structure of water: Entropy determines whether ions stick

Water molecules do not simply swirl around in complete disorder; they can form certain preferred structures. This scientific fact is often presented in entirely unscientific ways. For example, when people speak of an alleged “memory of water” or of “water clusters” as a possible explanation for homeopathy, among other things.

All of this has been refuted. But even though water is not a magical information storage medium, its ability to form short-lived structures can have important consequences. This has now been shown in a study by TU Wien, in collaboration with the University of Vienna and the University of Oslo, as part of the Cluster of Excellence “MECS.” The team investigated how easily charged particles can be held at a surface—a question that is important in many areas, such as research on batteries, fuel cells, and biological membranes. The new results show that this can only be understood if one takes into account the structures that water forms on nanosecond timescales.

The research is published in the journal Science Advances.

Bilayer antiferromagnet reveals photocurrent that flips with magnetic state

In recent years, atomically thin materials—crystals only a few atoms thick—have attracted growing attention because they can exhibit physical properties that do not appear in conventional bulk materials. Among them, atomically thin magnetic materials are particularly intriguing, as they can host unconventional magnetic states and offer new possibilities for spin-based electronic technologies.

In a Nature Materials study, researchers investigated the photocurrent response of a bilayer atomically thin antiferromagnet. In this material, spins are aligned within each atomic layer, while the spin orientations of the top and bottom layers are opposite. Depending on the relative spin configuration between the two layers, the system exhibits two distinct antiferromagnetic (AFM) states.

To explore how these magnetic states interact with light, the researchers fabricated devices by attaching electrodes to bilayer samples and illuminated the center of the material, away from the electrodes. They measured both the zero-bias photocurrent and current-voltage characteristics under illumination.

Scientists Created a Subatomic Particle That Defies Our Understanding of Physics

For decades, every known atomic and nuclear system has relied on at least two fundamental forces working in concert: the strong force binds protons and neutrons inside the nucleus, while electromagnetism holds electrons in orbit around it. Now, an international team of physicists has found the first experimental evidence of a nuclear system bound exclusively by the strong force—confirming a theoretical prediction made twenty years ago and opening a new window onto how matter acquires mass.

Creating a system held together by only one force required a particle with a special property: no electric charge. Ordinary atoms can’t do the job because their components—protons and electrons—are electrically charged, so electromagnetism is always in play. The Standard Model of particle physics, which describes three of the four fundamental forces (the strong force, the weak force, and electromagnetism —gravity isn’t included), predicts that electrically neutral mesons should be able to bind to a nucleus through the strong interaction alone. The eta prime meson (η′) is the ideal test case: it carries no electric charge, so it can’t be bound electromagnetically, and its unusually large mass makes it a uniquely sensitive probe of the strong force’s inner workings.

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