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Category: materials – Page 2

Traditionally, magnetic materials have been divided into two main categories: ferromagnets and antiferromagnets. Over the past few years, however, physicists have uncovered the existence of altermagnets, a new type of magnetic material that exhibits features of both antiferromagnets and ferromagnets.

Altermagnets are that have no net magnetization (i.e., their atomic magnetic moments cancel each other out), like antiferromagnets. Yet they also break spin degeneracy (i.e., the usual energy equality between spin-up and spin-down electrons), similarly to ferromagnets.

Researchers at Songshan Lake Materials Laboratory, Southern University of Science and Technology, the Hong Kong University of Science and Technology and other institutes in China recently set out to realize a layered altermagnet that can generate non-collinear spin current. The room-temperature metallic altermagnet they unveiled was outlined in a paper published in Nature Physics.

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An international research team led by Mayukh Kumar Ray, Mingxuan Fu, and Satoru Nakatsuji from the University of Tokyo, along with Collin Broholm from Johns Hopkins University, has discovered the anomalous Hall effect in a collinear antiferromagnet.

More strikingly, the anomalous Hall effect emerges from a non-Fermi liquid state, in which electrons do not interact according to conventional models. The discovery not only challenges the textbook framework for interpreting the anomalous Hall effect but also widens the range of antiferromagnets useful for information technologies.

The findings are published in the journal Nature Communications.

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Researchers have identified antiferromagnetism in a real icosahedral quasicrystal, reigniting interest in the quest to uncover antiferromagnetic quasicrystals. Quasicrystals (QCs) are a remarkable class of solid materials characterized by a unique atomic structure. Unlike conventional crystals, w

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In a physics first, a team including scientists from the National Institute of Standards and Technology (NIST) has created a way to make beams of neutrons travel in curves. These Airy beams (named for English scientist George Airy), which the team created using a custom-built device, could enhance neutrons’ ability to reveal useful information about materials ranging from pharmaceuticals to perfumes to pesticides—in part because the beams can bend around obstacles.

“We’ve known about these strange, self-steering wave patterns for a while, but until now, no one had ever made them with neutrons,” said NIST’s Michael Huber, one of the paper’s authors. “This opens up a whole new way to control neutron beams, which could help us see inside materials or explore some big questions in physics.”

A paper announcing the findings appears in Physical Review Letters.

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Knots are generally understood to form due to twists and turns of long, flexible materials that keep shoes on your feet or frustrate your attempts at hanging holiday decorations. A beam of light doesn’t sound like a material that can create a knot.

But it is.

Imagine throwing several rocks into a pond all at once. At a certain point on the water’s surface, the resulting ripple rings would all mix to form a complex pattern. Now imagine being able to control the shape and speed of each ring. With enough planning, you could get that mesh point to form in 3D on demand.

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A research team at POSTECH (Pohang University of Science and Technology) has developed a new alloy that maintains its strength and ductility across extreme temperatures ranging from −196 °C to 600 °C. The findings, which have drawn attention from the aerospace and automotive industries, were published in the journal Materials Research Letters. The team was led by Professor Hyoung Seop Kim from the Department of Materials Science and Engineering, Graduate Institute of Ferrous Technology, and Department of Mechanical Engineering.

Most metals used in everyday life are sensitive to temperature changes—metal doorknobs feel icy in winter and hot in summer. Consequently, conventional metal materials are typically optimized for performance within a narrow temperature range, limiting their effectiveness in environments with dramatic temperature fluctuations.

To overcome this challenge, the POSTECH research team introduced the concept of the “Hyperadaptor” and developed a nickel-based high-entropy alloy (HEA) that embodies this idea.

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Recent studies have revealed that electrons passing through chiral molecules exhibit significant spin polarization—a phenomenon known as chirality-induced spin selectivity. This effect stems from a nontrivial coupling between electron motion and spin within chiral structures, yet quantifying it remains challenging.

To address this, researchers at the Institute for Molecular Science (IMS) /SOKENDAI investigated an organic superconductor with chiral symmetry. They focused on nonreciprocity related to and observed an exceptionally large nonreciprocal transport in the , far exceeding theoretical predictions. Remarkably, this was found in an with inherently weak spin-orbit coupling, suggesting that chirality significantly enhances charge current-spin coupling with inducing mixed spin-triplet Cooper pairs.

The work is published in the journal Physical Review Research.

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