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Electronics are based on electrical charges being transported from one place to another. Electrons move, current flows, and signals are transmitted by applying an electrical voltage. However, there is also another way to manipulate electronic currents and signals: using the properties of the spin—the intrinsic magnetic moment of the electron. This is called “spintronics,” and it has become an increasingly important field in contemporary electronic research.

An international research team involving TU Wien and the Czech Academy of Sciences has now achieved an important breakthrough. They have managed to switch the spins in an antiferromagnetic material using surface strain. This could lead to an important new line of research in electronic technologies. The research is published in the journal Advanced Functional Materials.

“There are different types of magnetism,” explains Sergii Khmelevskyi from the Vienna Scientific Cluster Research Center, TU Wien. “The best known is ferromagnetism. It occurs when the atomic spins in a material are all aligned in parallel. But there is also the opposite, antiferromagnetism. In an antiferromagnetic material, neighboring atoms always have opposite spins.” Their effects therefore cancel each other out and no magnetic force can be detected from the outside.

Does dark matter reside in a deformed mirror universe of our own, where rules are different and atoms failed to form?

A team of physicists, including University of Massachusetts assistant professor Tigran Sedrakyan, recently announced in the journal Nature that they have discovered a new phase of matter. Called the “chiral Bose-liquid state,” the discovery opens a new path in the age-old effort to understand the nature of the physical world.

Under everyday conditions, matter can be a solid, liquid or gas. But once you venture beyond the everyday—into temperatures approaching absolute zero, things smaller than a fraction of an atom or which have extremely low states of energy—the world looks very different. “You find quantum states of matter way out on these fringes,” says Sedrakyan, “and they are much wilder than the three classical states we encounter in our everyday lives.”

Sedrakyan has spent years exploring these wild quantum states, and he is particularly interested in the possibility of what physicists call “band degeneracy,” “moat bands” or “kinetic frustration” in strongly interacting quantum matter.

The quantum ground state of an acoustic wave of a certain frequency can be reached by completely cooling the system. In this way, the number of quantum particles, the so-called acoustic phonons, which cause disturbance to quantum measurements, can be reduced to almost zero and the gap between classical and quantum mechanics bridged.

Over the past decade, major technological advances have been made, making it possible to put a wide variety of systems into this state. Mechanical vibrations oscillating between two mirrors in a resonator can be cooled to very low temperatures as far as the quantum ground state. This has not yet been possible for optical fibers in which high-frequency sound waves can propagate. Now researchers from the Stiller Research Group have taken a step closer to this goal.

A joint research project of Johannes Gutenberg University Mainz (JGU), the University of Siegen, Forschungszentrum Jülich, and the Elettra Synchrotron Trieste has achieved a new milestone for the ultra-fast control of magnetism. The international team has been working on magnetization configurations that exhibit chiral twisting. Chirality is a symmetry breaking, which occurs, for example, in nature in molecules that are essential for life. Chirality is also referred to as handedness, since hands are an everyday example of two items that—arranged in a mirror-inverted manner—cannot be superimposed onto each other. Magnetization configurations with a fixed chirality are currently investigated intensively due to their fascinating properties such as enhanced stability and efficient manipulation by current. These magnetic textures thus promise applications in the field of ultrafast chiral spintronics, for example in ultrafast writing and controlling of chiral topological magnetic objects such as magnetic skyrmions, i.e., specially twisted magnetization configurations with exciting properties.

The new insights published in Nature Communications shed light on the ultrafast dynamics after optical excitation of chiral spin structures compared to collinear spin structures. According to the researchers’ findings, the chiral order restores faster compared to the collinear order after excitation by an infrared laser.

The research team performed small angle X-ray scattering experiments on magnetic thin film samples stabilizing chiral magnetic configurations at the free electron laser (FEL) facility FERMI in Trieste in Italy. The facility provides the unique possibility to study the magnetization dynamics with femtosecond time resolution by using circular left polarized or right polarized light. The results indicate a faster recovery of chiral order compared to collinear magnetic order dynamics, which means that twists are more stable than straight magnetic configurations.

Researchers at Tohoku University and the Japan Atomic Energy Agency (JAEA) have discovered a new spintronic phenomenon—a persistent rotation of chiral-spin structure.

Their discovery was published in the journal Nature Materials on May 13, 2021.

Tohoku University and JAEA researchers studied the response of chiral-spin structure of a non-collinear antiferromagnet Mn₃Sn thin film to electron spin injection and found that the chiral-spin structure shows persistent rotation at zero magnetic field. Moreover, their frequency can be tuned by the applied current.

There is now a new addition to the magnetic family: thanks to experiments at the Swiss Light Source SLS, researchers have proved the existence of altermagnetism. The experimental discovery of this new branch of magnetism is reported in Nature and signifies new fundamental physics, with major implications for spintronics.

Magnetism is a lot more than just things that stick to the fridge. This understanding came with the discovery of antiferromagnets nearly a century ago. Since then, the family of magnetic materials has been divided into two fundamental phases: the ferromagnetic branch known for several millennia and the antiferromagnetic branch.

The experimental proof of a third branch of magnetism, termed altermagnetism, was made at the Swiss Light Source SLS, by an international collaboration led by the Czech Academy of Sciences together with Paul Scherrer Institute PSI.

Quantum computing engineers at UNSW Sydney have shown they can encode quantum information—the special data in a quantum computer—in four unique ways within a single atom, inside a silicon chip.

The feat could alleviate some of the challenges in operating tens of millions of quantum computing units in just a few square millimeters of a silicon quantum computer chip.

In a paper published in Nature Communications, the engineers describe how they used the 16 quantum ‘states’ of an antimony atom to encode quantum information.

CERN has announced that they are to release a cut-down version of their popular Hadron Collider for use in the home.

The Large Hadron Collider was built over twenty years ago, is housed in a 27-kilometre tunnel on the Switzerland – France border, and is used to smash particles together to see what happens.

The facility has proven tremendously successful, having smashed over thirty particles together since it was built.