Researchers demonstrate strong tunability and suppression of the spin signal and spin lifetime in graphene-based heterostructures

Researchers from Europe developed heterostructures built from graphene and topological insulators and have shown the strong tunability and suppression of the spin signal and spin lifetime in these structures.

Graphene topological insulator heterostructure channel (SEM photo)

Associate Professor Saroj Prasad Dash from Chalmers University of Technology explains that the advantage of using heterostructures built from two Dirac materials is tha graphene in proximity with topological insulators still supports spin transport, and concurrently acquires a strong spin–orbit coupling.

Researchers say that ferrimagnets-based spintronics devices could be faster than ferromagnets ones

Researchers from MIT, the Max-Born Institute, Technische Universität Berlin and the Deutsches Elektronen-Synchrotron (DESY) say ferrimagnets-based spintronics devices could be faster than ferromagnets ones.

Pt/Co44Gd56 ferrimagnetic schematic

Ferromagnets are traditional magnets - such as iron. Ferrimagnets are materials that have two types of ions with magnetic moments that are not equal - and are also polarized in opposite directions.Using these two ion types could be used, according to the researchers, to create smaller bits in magnetic memory as these will allow faster domain wall dynamics to occur.

Iron Oxide was found to be a promising magnon spintronics material

Researchers from the Johannes Gutenberg University Mainz, in cooperation with Utrecht University and the Center for Quantum Spintronics (QuSpin) at the Norwegian University of Science and Technology (NTNU), demonstrated that the antiferromagnetic material iron oxide is a promising magnon spintronics material.

An electrical current in a platinum wire creates a magnetic wave in the antiferromagnetic iron oxide

Iron oxide is a cheap material (it is the main material in rusted iron) that was shown to be able to carry magnon over long distances, with low access heat. For their demonstration, the researchers used used platinum wires on top of the insulating iron oxide. An electric current was introduced which led to the creation of magnons in the iron oxide.

BiSb films feature a colossal spin hall effect and high electrical conductivity

Researchers from the Tokyo Institute of Technology have developed a new thin film material made from bismuth-antimony (BiSb) that is a topological insulator that simultaneously achieves a colossal spin Hall effect and high electrical conductivity.

This material could be used as the basis of spin-orbit torque MRAM (SOT-MRAM). SOT-MRAM SOT-MRAM can overcome the limitation of spin-transfer torque in MRAM memories - and provide a much faster, denser and much more efficient memory technology. Up until now, though, no suitable material that features both high electrical conductivity and a high spin hall effect was developed.

Researchers find multi-layered Co/Ni films highly desirable materials for effective spin transfer torque

Researchers from the University of Lorraine in France report that following a comprehensive characterization of multilayers of cobalt (Co) and nickel (Ni), the material holds great promise for memory applications based on spin transfer torque (STT-MRAM).

Multi layered cobalt and nickel films for spintronics

It was already shown before that Co/Ni multilayers have very good properties for spintronics applications, but up until now it wasn't clear if the films have a sufficiently large intrinsic spin polarization, which is necessary to create and maintain spin-polarized currents in spintronic devices. It was now shown that the films have a spin polarization of about 90% - which is similar to the best spintronic materials.

Researchers develop an all-electric method to measure the spin texture of topological insulators

Researchers from Singapore's NUS and the University of Missouri developed a new all-electric method to measure the spin texture of topological insulators. The researchers say that this method could lead to an easier (and cheaper) methods of developing spintronics devices.

Spin Texture measurements of Topological Insulators (NUS)

The new work revealed a close relation between the spin texture of topological surface states (TSS) and a new kind of magneto-resistance. The researchers observed the second order nonlinear magneto-resistance in a prototypical 3D TI Bi2Se3 films, and showed that it is sensitive to TSS. In contrast with conventional magneto-resistances, this new magneto-resistance shows a linear dependence on both the applied electric and magnetic fields.

Zero-Field Switching effect discovered in cobalt-iron-boron

Researchers from Johns Hopkins University and the US NIST discovered that magnetisation in a cobalt-iron-boron layer could be flipped between stable states using only electric current, without an external magnetic field. The researchers call this effect Zero-Field Switching (ZFS).

ZFE in cobalt-iron-boron layer (JHU / NIST)

The researchers say that this effect was not theoretically predicted, as all previous devices of this type have required a magnetic field or other more complex measures to change the material's magnetisation.