Memory

Researchers from Tohoku University and Toho University have demonstrated chirality switching by electric current pulses at room temperature in a thin-film MnAu₂ helimagnetic conductor. The team also succeeded in detecting the chirality at zero magnetic fields by means of simple transverse resistance measurement utilizing the spin Berry phase in a bilayer device composed of MnAu₂ and a spin Hall material Pt. These results may pave the way to helimagnet-based spintronics. 

Helimagnetic structures, in which the magnetic moments are spirally ordered, host an internal degree of freedom called chirality corresponding to the handedness of the helix. The chirality seems quite robust against disturbances and is therefore promising for next-generation magnetic memory. While the chirality control was recently achieved by the magnetic field sweep with the application of an electric current at low temperature in a conducting helimagnet, problems such as low working temperature and cumbersome control and detection methods have to be solved in practical applications.

Researchers at North Carolina State University, University of Illinois at Urbana-Champaign, Duke University and Sivananthan Laboratories have relied on a printable organic polymer, that assembles into chiral structures when printed, to reliably measure the amount of charge produced in spin-to-charge conversion within a spintronic material at room temperature. 

The polymer’s tunable qualities and versatility make it desirable not only for less expensive, environmentally friendly, printable electronic applications, but also for use in understanding chirality and spin interactions more generally.

The EU project 2DSPIN-TECH aims to pave the way for significantly faster and more energy-efficient computer memories. Last week, the project kickoff event took place, with seven partners and €4 million in funding. The project spans three years and is conducted within the framework of the EU’s Graphene Flagship, a multibillion-dollar initiative launched over a decade ago to stimulate research and innovation in graphene and other two-dimensional materials.

“Our ambition is to create novel spintronic memory devices based on two-dimensional quantum materials, significantly reducing energy consumption, promoting sustainability, and enhancing the overall performance of computer memories. This is crucial for the future of information technology,” says Saroj Dash, Professor of quantum component physics at Chalmers University of Technology and coordinator of 2DSPIN-TECH.

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 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?"

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 from The Ohio State University in the U.S, Uppsala University in Sweden and the UK's University of Exeter have used a novel technique to confirm a previously undetected physics phenomenon that could be used to improve data storage in the next generation of computer devices.

Spintronic memories, like those used in some high-tech computers and satellites, use magnetic states generated by an electron's intrinsic angular momentum to store and read information. Depending on its physical motion, an electron's spin produces a magnetic current. Known as the "spin Hall effect," this has key applications for magnetic materials across many different fields, ranging from low power electronics to fundamental quantum mechanics.

Researchers from Tohoku University, Chinese Academy of Sciences (CAS), Guangxi Normal University, Kyushu University and Japan Atomic Energy Agency have reported a significant breakthrough which could revolutionize next-generation electronics by enabling non-volatility, large-scale integration, low power consumption, high speed, and high reliability in spintronic devices.

Spintronic devices, such as magnetic random access memory (MRAM), utilize the magnetization direction of ferromagnetic materials for information storage and rely on spin current, a flow of spin angular momentum, for reading and writing data. Conventional semiconductor electronics have faced limitations in achieving these qualities. However, the emergence of three-terminal spintronic devices, which employ separate current paths for writing and reading information, presents a solution with reduced writing errors and increased writing speed. Nevertheless, the challenge of reducing energy consumption during information writing, specifically magnetization switching, remains a critical concern.

Researchers from MIT and Tohoku University have reported a representative effect of the anomalous dynamics at play when an electric current is applied to a class of magnetic materials called non-collinear antiferromagnets. 

Non-collinear antiferromagnets have properties distinct from conventional magnetic materials—in traditional collinear magnets, the magnetic moments align in a collinear fashion. However, in non-collinear ones, the moments form finite angles between one another. Scientists describe these non-collinear arrangements as a single order parameter, the octupole moment, which has been demonstrated to be critical for determining the exotic properties of the materials.

Researchers from the Hebrew University of Jerusalem in Israel have made a recent discovery that could change the face of spintronics research.

A spintronics device developed by Professor Capua's lab

They discovered that the most important equation used to describe magnetization dynamics, namely the Landau-Lifshitz-Gilbert (LLG) equation, also applies to the optical domain. Consequently, they found that the helicity-dependent optical control of the magnetization state emerges naturally from their calculations. This is a very surprising result since the LLG equation was considered to describe much slower dynamics and it was not expected to yield a meaningful outcome also at the optical limit.