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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.

Physicists create hybrid light-matter particles that interact strongly enough to compute

Eighty years ago, Penn researchers J. Presper Eckert and John Mauchly launched the age of electronic computing by harnessing electrons to solve complex numerical problems with ENIAC, the world’s first general-purpose electronic computer. Today, that same architecture still underlies general computing, but electrons are beginning to show their limits. Because they carry a charge, they lose energy as heat, encounter resistance as they move through materials, and become harder to manage as chips incorporate more transistors and handle larger volumes of data.

With artificial intelligence pushing today’s hardware to process, move, and cool more, Penn physicists led by Bo Zhen in the School of Arts & Sciences are looking to the electron’s massless counterpart, the photon, to shoulder more of the load.

“Because they are charge-neutral and have zero rest mass, photons can carry information quickly over long distances with minimal loss, dominating communications technology,” explains Li He, co-first author of a paper published in Physical Review Letters and a former postdoctoral researcher in the Zhen Lab. “But that neutrality means they barely interact with their environment, making them bad at the sort of signal-switching logic that computers depend on.”

Exploiting interfacial ionic mobility to make heat-moldable nanoparticle aggregates

If you have ever warped a cheap plastic cup by pouring coffee into it, then you have witnessed thermoplasticity in action. Thermoplasticity is the ability of a material to become pliable under heating. In industry, thermoplasticity is exploited to form materials into complex shapes using heat. However, some materials, such as aggregates of nanoparticles, are not thermoplastic and cannot be easily processed without affecting their particle morphology and properties.

However, researchers at The University of Osaka have been able to use heat to shape nanoparticle aggregates, specifically cellulose nanofibers (CNFs) derived from wood pulp. This exciting advance, showcasing the mechanical and thermal potential of nanoparticles, is published in Science Advances.

String theory is uniquely derived from basic assumptions about the universe, physicists show

If you could take an apple and break it into smaller and smaller parts, you would find molecules, then atoms, followed by subatomic particles like protons and the quarks and gluons that make them up. You might think you hit the bottom, but, according to string theorists, if you keep going to even smaller scales—about a billion billion times smaller than a proton—you will find more: tiny vibrating strings.

Developed in the 1960s, string theory proposes that everything in the universe is made from invisible strings. The theory arose as a possible solution to the problem of “quantum gravity,” the quest to align quantum mechanics, which describes our world at the smallest scales, with the general theory of relativity, which explains how our universe works on the largest scales (and includes gravity). Researchers have tried to reconcile the two theories—asking, for example, how gravity behaves in the quantum realm—but their equations go berserk, or in mathematical terms, go to infinity.

String theory is a mathematical solution that tames the unruly infinities. It purports that all particles, including the graviton—the hypothetical particle believed to convey the force of gravity—are generated by very small vibrating strings. The math behind string theory requires the strings to vibrate in at least 10 dimensions, rather than the four we live in (three for space and one for time), which is one of the reasons some scientists are not convinced that string theory is correct. But perhaps the biggest challenge for the theory is the ultrahigh energies required for testing it: Such an experiment would require a particle collider the size of a galaxy.

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