Ferromagnetism

Researchers at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) have partnered with NTNU, the Norwegian University of Science and Technology in Trondheim, and the Institute of Nuclear Physics in the Polish Academy of Sciences to develop a method that facilitates the manufacture of particularly efficient magnetic nanomaterials in a relatively simple process based on inexpensive raw materials. 

Using a highly focused ion beam, they imprint magnetic nanostrips consisting of tiny, vertically aligned nanomagnets onto the materials. This geometry makes the material highly sensitive to external magnetic fields and current pulses.

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.

A team of scientists from the Hebrew University of Jerusalem (Israel), the Weizmann Institute of Science (Israel), Pennsylvania State University (U.S.A.), and the University of Manchester (UK) has developed a new way to detect subtle magnetic signals in common metals like copper, gold, and aluminium - using nothing more than light and a clever technique. Their research could pave the way for advances in many fields, from smartphones to quantum computing.

For over a century, scientists have known that electric currents bend in a magnetic field - a phenomenon known as the Hall effect. In magnetic materials like iron, this effect is strong and well understood. But in ordinary, non-magnetic metals like copper or gold, the effect is much weaker. In theory, a related phenomenon - the optical Hall effect - should help scientists visualize how electrons behave when light and magnetic fields interact. But at visible wavelengths, this effect has remained far too subtle to detect. The scientific world has long since believed in its existence, but lacked the tools to measure it.

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 Osaka University have reported a technique for recovering magnetism in a degraded spintronics device. This method can be applied to improve the robustness of next-generation semiconductor memory.

Spintronics exploits the spin (and charge) of electrons to process and store memory, which is achieved practically by stacking layers of thin material films that behave differently under the influence of a magnetic field. “These devices can be non-volatile, low-power, and robust, but the manufacturing process can cause their magnetic properties to deteriorate,” explains Tomohiro Koyama, lead author of the study. The thin films required for these devices are often formed via sputtering, in which atoms are extracted and deposited onto a substrate. This process, however, can often lead to the magnetic layer becoming oxidized, spoiling its magnetic properties.

Researchers from the University of Minnesota−Twin Cities, MIT, Gwangju Institute of Science and Technology, Sungkyunkwan University and Pusan National University have discovered surprising magnetic behavior in one of the thinnest metallic oxide materials ever made. This could pave the way for the next generation of faster and smarter spintronic and quantum computing devices.

Using an advanced materials growth technique called hybrid molecular beam epitaxy, the researchers created ultra-thin layers of RuO₂, a compound typically known for its metallic but nonmagnetic behavior. By applying epitaxial strain to these atomically thin layers, they were able to induce magnetic properties in a material that is otherwise nonmagnetic.

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.”

A joint research team, led by Professor Jeong Myung-hwa from Sogang University and Professors Lee Kyung-jin and Kim Gap-jin from the Korea Advanced Institute of Science and Technology (KAIST), has captured, for the first time, the phenomenon of quantum mechanical spin pumping occurring at room temperature.

With charge current,  as current flows, electrons collide with atoms inside the material, generating heat and increasing energy consumption. This lowers the efficiency of current generation. To address this, researchers worldwide are conducting studies on creating electronic devices using spin current. The research team focused on the spin pumping phenomenon where spin moves from a ferromagnet to a non-magnetic material due to precession.

Researchers from the National University of Singapore (NUS), working with teams from University of California, Kyoto University and others, have reported a breakthrough in the development of next-generation graphene-based quantum materials, opening new horizons for advancements in quantum electronics.

The innovation involves a novel type of graphene nanoribbon (GNR) named Janus GNR (JGNR). The material has a unique zigzag edge, with a special ferromagnetic edge state located on one of the edges. This unique design enables the realization of one-dimensional ferromagnetic spin chain, which could have important applications in quantum electronics and quantum computing.

Researchers at the Research Center for Materials Nanoarchitectonics (MANA) recently proposed a method to create ferroelectric-ferromagnetic materials, opening doors to advancing spintronics and memory devices.

In 1831, Michael Faraday discovered the fundamental connection between electricity and magnetism, demonstrating that a changing magnetic field induces electric current in a conductor. In a recent study, MANA researchers proposed a method for designing ferroelectric-ferromagnetic (FE-FM) materials, which exhibit both ferroelectric and ferromagnetic properties, enabling the manipulation of magnetic properties using electric fields and vice versa. Such materials are highly promising for spintronics and memory devices. The advantage of FE-FM materials, extremely rare in nature, is their ability to achieve the cross-control by relatively low electric and magnetic fields. The study, led by Principal Researcher Igor Solovyev from MANA, NIMS, included contributions from Dr. Ryota Ono from MANA, NIMS, and Dr. Sergey Nikolaev from the University of Osaka, Japan.