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Researchers from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences revealed that not all forms of quantum nonlocality guarantee intrinsic randomness. They demonstrated that violating two-input Bell inequalities is both necessary and sufficient for certifying randomness, but this equivalence breaks down in scenarios involving multiple inputs. The study is published in Physical Review Letters.

Quantum mechanics is inherently probabilistic, and this intrinsic has been leveraged for applications like random number generation. However, ensuring the security of these random numbers in real-world scenarios is challenging due to potential vulnerabilities in the devices used.

Bell nonlocality, where particles exhibit correlations that cannot be explained by classical physics, offers a way to certify randomness without trusting the devices. Previous studies have shown that violating Bell inequalities can certify randomness in simple two-input, two-output systems. However, the applicability of this principle to more complex, multiple-input, multiple-output (MIMO) systems has been unclear.

In a new paper, researchers at North Carolina State University show proof of concept for a system that—in a single cycle—actively removes microplastics from water.

The findings, described in the journal Advanced Functional Materials, hold the potential for advances in cleansing oceans and other bodies of water of tiny plastics that may harm human health and the environment.

“The idea behind this work is: Can we make the cleaning materials in the form of soft particles that self-disperse in water, capture microplastics as they sink, and then return to the surface with the captured microplastic contaminants?” said Orlin Velev, the S. Frank and Doris Culberson Distinguished Professor of Chemical and Biomolecular Engineering at NC State and corresponding author of the paper.

Highly charged heavy ions form a very suitable experimental field for investigating quantum electrodynamics (QED), the best-tested theory in physics describing all electrical and magnetic interactions of light and matter. A crucial property of the electron within QED is the so-called g factor, which precisely characterizes how the particle behaves in a magnetic field.

Recently, the ALPHATRAP group led by Sven Sturm in the division of Klaus Blaum at the Max-Planck-Institut für Kernphysik (MPIK) in Heidelberg measured the g factor of hydrogen-like tin ions on a precision level of 0.5 parts per billion, which is like measuring the distance from Cologne to Frankfurt with precision down to the thickness of a human hair. This is a stringent test of QED for the simplest atomic system, just like conventional hydrogen but with a much higher electric field experienced by the electron due to the charge of 50 protons inside the tin nucleus.

In a new study published in Physical Review Letters, researchers have now tackled highly charged boron-like tin ions with only five remaining electrons. The goal is to study the inter-electronic effects in the boron-like configuration. So far, the only boron-like g factor has been measured with high precision for argon ions with a proton number Z of 18. However, the nucleus is not a point charge like the electron and its charge distribution leads to finite nuclear size corrections—another challenge for precision experiments.

On March 24, at the annual Rencontres de Moriond conference taking place in La Thuile, Italy, the LHCb collaboration at CERN reported a new milestone in our understanding of the subtle yet profound differences between matter and antimatter.

In its analysis of large quantities of data produced by the Large Hadron Collider (LHC), the international team found overwhelming evidence that particles known as baryons, such as the protons and neutrons that make up , are subject to a mirror-like asymmetry in nature’s fundamental laws that causes matter and antimatter to behave differently.

The discovery provides new ways to address why the that make up matter fall into the neat patterns described by the Standard Model of particle physics, and to explore why matter apparently prevailed over antimatter after the Big Bang. The paper is available on the arXiv preprint server.

Researchers say they are finally unraveling the effects of ultrafast lasers that can change material states in attoseconds —one-billionth of one-billionth of a second—the time required to complete one light wave’s optical cycle.

The new Israeli research opens up new avenues for scientists to observe light closely in laboratory settings. Under these conditions, a wave crosses a hydrogen atom in a single attosecond, compared to the time required for light to move from Earth to the Moon.

Beyond its immediate use, the development may drive future speed advancements in communications and computing by increasing researchers’ understanding of high-speed quantum light and matter interactions.

The arrangement of small molecules—known as ligands—around transition metal atoms affects how the metal atoms behave. This is important because transition metals are used as catalysts in the synthesis of a wide range of important materials.

Now, in a study published in the Journal of the American Chemical Society, researchers from the University of Osaka have reported a chemical bond that hadn’t been reported before: complexes of , a metal, with simple containing , a non-metal.

Transition metals are known to form complexes with ligands containing atoms from group 13 elements, including aluminum, gallium, and indium. These are known as Z-type ligands, and they can accept electrons from a metal. However, boron, the smallest element in group 13, has only been shown to do this with the support of additional ligands that help approach metals to the boron center.

What happens when a quantum physicist is frustrated by the limitations of quantum mechanics when trying to study densely packed atoms? At EPFL, you get a metamaterial, an engineered material that exhibits exotic properties.

That frustrated physicist is Ph.D. student Mathieu Padlewski. In collaboration with Hervé Lissek and Romain Fleury at EPFL’s Laboratory of Wave Engineering, Padlewski has built a novel acoustic system for exploring condensed matter and their macroscopic properties, all the while circumventing the extremely sensitive nature that is inherent to . Moreover, the can be tweaked to study properties that go beyond solid-state physics. The results are published in Physical Review B.

“We’ve essentially built a playground inspired by that can be adjusted to study various systems. Our metamaterial consists of highly tunable active elements, allowing us to synthesize phenomena that extend beyond the realm of nature,” says Padlewski. “Potential applications include manipulating waves and guiding energy for telecommunications, and the setup may one day provide clues for harvesting energy from waves for instance.”

A hidden quantum wave may keep particles moving, even when everything else freezes. Researchers discovered that phasons, a type of low-temperature quasiparticle found in crystal lattices, allow interlayer excitons to move, even at temperatures where motion is expected to stop.

The standard model of particle physics is our best theory of the elementary particles and forces that make up our world: particles and antiparticles, such as electrons and positrons, are described as quantum fields. They interact through other force fields, such as the electromagnetic force that binds charged particles.

To understand the behavior of these quantum fields—and with that, our universe—researchers perform complex computer simulations of quantum field theories. Unfortunately, many of these calculations are too complicated for even our best supercomputers and pose great challenges for quantum computers as well, leaving many pressing questions unanswered.

Using a novel type of quantum computer, Martin Ringbauer’s experimental team at the University of Innsbruck, and the theory group led by Christine Muschik at IQC at the University of Waterloo, Canada, report in Nature Physics on how they have successfully simulated a complete quantum field theory in more than one spatial dimension.