Higher-order topological insulators, or HOTIs, have attracted attention for their ability to conduct electricity along one-dimensional lines on their surfaces, but this property is quite difficult to experimentally distinguish from other effects. 

By instead studying the interiors of these materials from a different perspective, a team of researchers at the University of Illinois at Urbana-Champaign, Dublin Institute for Advanced Studies, Chinese Academy of Sciences and additional collaborators has identified a surface signature that is unique to HOTIs that can determine how light reflects from their surfaces. 

Researchers at the National Synchrotron Light Source II at Brookhaven National Laboratory, University of California Davis, University of Colorado Springs, Stockholm University, National Institute of Standards and Technology, University of California San Diego, Ca’ Foscari University of Venice, and Elettra Sincrotrone Trieste have conducted an experiment with magnetic materials and ultrafast lasers that could advance energy-efficient data storage.

"We wanted to study the physics of light-magnet interaction," said Rahul Jangid, who led the data analysis for the project while earning his Ph.D. in materials science and engineering at UC Davis under associate professor Roopali Kukreja. "What happens when you hit a magnetic domain with very short pulses of laser light?"

Researchers at Japan's RIKEN have conducted an experiment that could help the development of new energy-efficient spintronics devices. They used heat and magnetic fields to create transformations between spin textures—magnetic vortices and antivortices known as skyrmions and antiskyrmions—in a single crystal thin plate device. What's even more important is that they achieved this at room temperature.

Skyrmions and antiskyrmions, which are textures that exist within special magnetic materials involving the spin of the electrons in the material, are an active area of research, as they could be used for next-generation memory devices, for example, with skyrmions acting as a "1" bit and antiskyrmions a "0" bit. In the past, scientists have been able to move them in a variety of ways, and to create transformations between them using electric current. However, because current electronic devices consume electrical power and produce waste heat, the researchers in the group, led by Xiuzhen Yu at the RIKEN Center for Emergent Matter Science, decided to see if they could find a way to create the transformations using heat gradients.

A Japanese research team, led by Jun Okabayashi from the University of Tokyo, including Associate Professor Yoshihiro Gohda from Tokyo Tech and Osaka University researchers, recently revealed a strain-induced orbital control mechanism in interfacial multiferroics. 

Controlling the direction of magnetization using low electric field is important for achieving efficient spintronic devices. In spintronics, properties of an electron's spin or magnetic moment are used to store information. The electron spins can be manipulated by straining orbital magnetic moments to create a high-performance magnetoelectric effect.

Researchers at Japan's Tokyo Institute of Technology (Tokyo Tech) have demonstrate the concept of Berry phase monopole engineering of the spin Hall effect in non-centrosymmetric silicide TaSi₂.

Image credit: Tokyo Tech

Spin-transfer torque is an important phenomenon that enables ultrafast and low-power spintronic devices. Recently, however, spin-orbit torque (SOT) has emerged as a promising alternative to spin-transfer torque. Many studies have investigated the origin of SOT, showing that in non-magnetic materials, a phenomenon called the spin Hall effect (SHE) is key to achieving SOT. In these materials, the existence of a “Dirac band” structure, a specific arrangement of electrons in terms of their energy, is important to achieving large SHE. This is because the Dirac band structure contains “hot spots” for the Berry phase, a quantum phase factor responsible for the intrinsic SHE. Thus, materials with suitable Berry phase hot spots are key to engineering the SHE.

Researchers at Tohoku University and the University of California, Santa Barbara, have shown a proof-of-concept energy-efficient computer compatible with current AI. It utilizes a stochastic behavior of nanoscale spintronics devices and is particularly suitable for probabilistic computation problems such as inference and sampling.

The team presented the results at the IEEE International Electron Devices Meeting (IEDM 2023) on December 12, 2023.

Scientists at the University of Wisconsin–Madison, University of California, Cornell University, University of Nebraska, Arizona State University and Tsinghua University have found a unique property of the material Ba(Pb,Bi)O₃: it exhibits extremely high spin orbit torque, a property useful in the field of spintronics. The materials was previously found to act as a rare type of superconductor that could operate at higher temperatures. 

The combination of these two properties makes this and similar materials potentially important in developing the next generation of fast, efficient memory and computing devices.

Researchers at the National University of Singapore (NUS), University of Science and Technology of China and the National Institute for Materials Science in Japan have developed a way to induce and directly quantify spin splitting in two-dimensional materials. 

Using this concept, they have experimentally achieved large tunability and a high degree of spin-polarization in graphene. This research achievement can potentially advance the field of two-dimensional (2D) spintronics, with applications for low-power electronics.

Researchers from Beijing University of Technology, South China University of Technology, Forschungszentrum Jülich and Uppsala University have reported the first experimental evidence of hopfions, which are magnetic spin structures predicted decades ago that have become a fascinating research topic in recent years.

The team used transmission electron microscopy to observe hopfions forming coupled states with skyrmion strings in B20-type FeGe plates. They provided a protocol for nucleating such hopfion rings, which they verified using Lorentz imaging and electron holography. The scientists' results are said to be highly reproducible and in full agreement with micromagnetic simulations. 

Dr. Darren M. Graham, an associate professor from the University of Manchester, has given an interesting talk recently, titled "Exploiting magnetic anisotropy: realizing magnetic-field-free spintronic THz emitters and polarization control".