February 2024

One way of processing information in spintronics is to use the magnetic vortices called skyrmions or, alternatively, their still little understood and rarer cousins called 'merons'. Both are collective topological structures formed of numerous individual spins. Merons have to date only been observed in natural antiferromagnets, where they are difficult to both analyze and manipulate.

Working in collaboration with teams at Tohoku University in Japan and the ALBA Synchrotron Light Facility in Spain, researchers of Johannes Gutenberg University Mainz (JGU) have been the first to demonstrate the presence of merons in synthetic antiferromagnets and thus in materials that can be produced using standard deposition techniques.

Researchers at Newcastle University, National University of Singapore (NUS) and Japan's National Institute for Materials Science have reported a significant discovery in the field of spintronics based on the unique properties of an ultrathin, two-dimensional material called black phosphorus and how it transports spinning electrons.

Spintronics utilizes the intrinsic spin of electrons to create more energy-efficient devices. Electrons have a spin state of “up” or “down” causing the electrons to act like tiny magnets and manipulating this state has been seen by researchers as crucial for achieving lower power operation in electronic devices. This is because the spin motion of electrons inherently dissipates far less heat than the movement of electrical charge used in traditional electronics. Whilst the phenomenon of spin itself has been widely studied, the challenge has been finding a material with the optimal properties for creating the channels that transport spins.

Researchers at the Czech Academy of Sciences, Institut Polytechnique de Paris, Vienna Technical University (TU Wien), Charles University, Malvern Panalytical B.V., Nuclear Physics Institute CAS and the European Commission's Joint Research Centre (JRC) recently made an important step that could advance the field of spintronics: they managed to switch the spins in an antiferromagnetic material using surface strain. 

"There are different types of magnetism," explains Sergii Khmelevskyi from the Vienna Scientific Cluster Research Center, Vienna Technical University. "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.

Researchers have conducted experiments at the Swiss Light Source SLS that resulted in proof of the existence of a new type of magnetism: altermagnetism. The experimental discovery of this new branch of magnetism could signify new fundamental physics, with major implications for spintronics.

Since the discovery of antiferromagnets nearly a century ago, 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 by an international collaboration led by the Czech Academy of Sciences together with Paul Scherrer Institute PSI. The fundamental magnetic phases are defined by the specific spontaneous arrangements of magnetic moments—or electron spins—and of atoms that carry the moments in crystals.

An international team of researchers has identified a novel state of matter, distinguished by chiral currents at the atomic level. This discovery challenges traditional understandings of magnetic materials and opens up new doors for quantum material applications.

Chirality, a property indicating that a structure cannot be superimposed onto its mirror image, is crucial across various scientific fields, notably in understanding DNA's structure. The research group, led by Federico Mazzola from Ca' Foscari University of Venice, observed these chiral currents through interactions between light and matter. Specifically, they demonstrated that electrons could be ejected from a material's surface with a distinct spin state by employing suitably polarized photons.

An interdisciplinary collaboration of researchers from South Korea and Singapore recently reported a significant advance towards achieving spin-polarized van der Waals heterostructures. The team designed a spin-selective memtransistor device using single-layer graphene deposited on the antiferromagnetic van der Waals magnetic insulator CrI₃. 

Transport measurements combined with first-principles calculations provide unprecedented insights into tailoring reciprocal magnetic proximity interactions to generate and probe proximitized magnetism in graphene at room temperature.

Researchers have devised a new ultrafast method for controlling magnetic materials, that may enable next-generation information processing technologies.

A possible solution for building faster systems for processing is to use patterns of electron spins, called spin waves, to transfer and process information much more rapidly than in conventional computers. So far, a major challenge has been in manipulating these ultrafast spin waves to do useful work. Announcing a significant step forward, researchers from The University of Texas at Austin and MIT have developed a method to precisely manipulate these ultrafast spin waves using tailored light pulses. Their findings are detailed in two studies in Nature Physics, led by MIT graduate student Zhuquan Zhang, University of Texas at Austin postdoctoral researcher Frank Gao, MIT’s professor of chemistry Keith Nelson and UT Austin assistant professor of physics Edoardo Baldini.