Spin current

Researchers from the University of British Columbia, Max Planck Institute for Solid State Research and University of Nevada have proposed a new class of quantum materials - superconducting altermagnets - that could carry persistent spin-polarized currents with zero dissipation, marking a potential breakthrough in superconducting spintronics. 

The team's theoretical study shows how these materials can host spin supercurrents that remain stable even in the presence of spin-orbit coupling (SOC) and magnetic disorder - conditions that usually extinguish spin transport in normal metals.

Researchers from The University of Manchester have discovered that interfacing magnetic thin films with atomically thin molybdenum disulfide (MoS₂) fundamentally alters how these films dissipate energy - a step toward practical, wafer‑scale 2D spintronic devices.

Using ferromagnetic resonance (FMR) spectroscopy, the team investigated spin pumping and damping mechanisms in large‑area transition‑metal dichalcogenide (TMD)-ferromagnet heterostructures, specifically MoS₂–Ni₀.₈Fe₀.₂ bilayers with varying ferromagnetic thickness. The MoS₂ was grown using chemical vapor deposition (CVD), an industry‑compatible approach that allows uniform monolayer and bilayer coverage across wafer‑scale samples.

Researchers from the Institut Català de Nanociència i Nanotecnologia (ICN2), CSIC and BIST have reported a theoretical framework and numerical confirmation for fully efficient spin-charge interconversion in graphene. Efficient conversion of charge current into spin current is a central objective in spintronics, and the intrinsic properties of graphene make it an attractive platform to explore this phenomenon.

Joaquín Medina Dueñas, Santiago Giménez de Castro, Jose H. Garcia, and Stephan Roche from ICN2 demonstrate that a complete conversion can be achieved by controlling the coupling between spin and pseudospin degrees of freedom. The study shows that a combined spin-pseudospin operator remains conserved in graphene, enabling fully efficient spin-charge conversion through the Rashba-Edelstein effect. The results also reveal the presence of a spin Hall effect that is resilient to disorder, indicating a stable mechanism for spin transport in realistic graphene systems.

A team of University of Minnesota researchers recently demonstrated a more efficient way to control magnetization in tiny electronic devices using a material called Ni₄W–a combination of nickel and tungsten. 

The team found that this low-symmetry material produces powerful spin-orbit torque (SOT)—a key mechanism for manipulating magnetism in next-generation memory and logic technologies.

Researchers from Cornell University, Columbia University and Japan's National Institute for Materials Science have demonstrated direct electrical detection of antiferromagnetic resonance in structures on the few-micrometer scale using spin-filter tunneling in PtTe₂/bilayer CrSBr/graphite junctions in which the tunnel barrier is the van der Waals antiferromagnet CrSBr. 

Ferromagnetic materials have been in use in technologies like magnetic hard drives, magnetic random access memories and oscillators for many years. But antiferromagnetic materials, if only they could be harnessed, hold even greater potential: ultra-fast information transfer and communications at much higher frequencies. Now, the researchers' recent work is a step in that direction. Their work could be beneficial for both detecting and controlling the motion of spins within antiferromagnets using 2D antiferromagnetic materials and tunnel junctions.

Researchers at Germany's University of Münster have designed low-loss spin-wave waveguides in yttrium iron garnet thin films using silicon ion implantation, creating an amorphous waveguide cladding. The team's spin waveguide network processes information with far less energy and could offer a promising alternative to power-hungry electronics.

The rapid rise in AI applications has placed increasingly heavy demands on energy infrastructures, causing researchers to look for energy-saving solutions for AI hardware. One promising idea is the use of so-called spin waves to process information. The team in this work, led by physicist Prof. Rudolf Bratschitsch (Münster), has developed a new way to produce waveguides in which the spin waves can propagate particularly far. They have not only created the largest spin waveguide network to date, but also succeeded in specifically controlling the properties of the spin wave transmitted in the waveguide. For example, they were able to precisely alter the wavelength and reflection of the spin wave at a certain interface. 

Scientists from TU Delft National Institute for Materials Science, University of Valencia, University of Regensburg and Harvard University have observed quantum spin currents in graphene for the first time without using magnetic fields. These currents are important for spintronics and could promote technologies like quantum computing and advanced memory devices.

Quantum physicist Talieh Ghiasi has demonstrated the quantum spin Hall (QSH) effect in graphene for the first time without any external magnetic fields. The QSH effect causes electrons to move along the edges of the graphene without any disruption, with all their spins pointing in the same direction. “Spin is a quantum mechanical property of electrons, which is like a tiny magnet carried by the electrons, pointing up or down”, Ghiasi explains. “We can leverage the spin of electrons to transfer and process information in so-called spintronics devices. Such circuits hold promise for next-generation technologies, including faster and more energy-efficient electronics, quantum computing, and advanced memory devices.”

Researchers at MIT, Università degli Studi "Gabriele d'Annunzio", Yale University, Drexel University, Rutgers University and University of Illinois Urbana-Champaign have demonstrated a new form of magnetism that could one day be harnessed to build faster, denser, and less power-hungry spintronic memory chips.

The new magnetic state is a hybrid of two main forms of magnetism: the ferromagnetism and antiferromagnetism. Now, the MIT team has demonstrated a new form of magnetism, termed “p-wave magnetism.”

In 2023, EPFL researchers succeeded in sending and storing data using charge-free magnetic waves called spin waves, rather than traditional electron flows. The team from the Lab of Nanoscale Magnetic Materials and Magnonics, led by Dirk Grundler, used radiofrequency signals to excite spin waves enough to reverse the magnetization state of tiny nanomagnets. When switched from 0 to 1, for example, this allows the nanomagnets to store digital information; a process used in computer memory, and more broadly in information and communication technologies. This work was a big step toward sustainable computing, because encoding data via spin waves (whose quasiparticles are called magnons) could eliminate the energy loss, or Joule heating, associated with electron-based devices. But at the time, the spin wave signals could not be used to reset the magnetic bits to overwrite existing data.

Now, Grundler's lab at EPFL, in collaboration with colleagues from Beihang University, ETH Zurich, Japan Atomic Energy Agency, Chinese Academy of Sciences and China's International Quantum Academy, have published a study that could make such repeated encoding possible. Specifically, they report unprecedented magnetic behavior in hematite: an iron oxide compound that is earth-abundant and much more environmentally friendly than materials currently used in spintronics.

Researchers from Beihang University and Freie Universität Berlin have developed a spintronic THz emitter with a microscale stripe pattern that enables the modulation of chirality during THz wave generation. Unlike traditional THz sources that rely on external optical components, this emitter incorporates polarization tuning directly into its design, streamlining the technology and enhancing its capabilities.

The emitter comprises thin-film layers of tungsten, cobalt-iron-boron, and platinum. When exposed to ultrafast laser pulses, the material generates a spin current, which is converted into an electrical charge through the inverse spin Hall effect.