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.

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 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.

Researchers report room temperature spin-orbit torque switching using a topological insulator

Researchers from NUS have demonstrated for the first time room temperature magnetization switching driven by giant spin-orbit torques (SOT) in topological insulator/conventional ferromagnetic heterostructures with an extremely low current density.

SOT switching using Bi2Se3 on NiFe (NUS)

The researchers believe that such switching that uses so little power could be used to scale up spintronics devices. The researchers achieved the switching using an 8-nm layer of Bi2Se3 grown on top of a 6 nm layer of NiFe, a widely used ferromagnet.

Researchers manage to generate and manipulate the surface spin current in topological insulators

Researcherrs from Likoping University in Sweden demonstrated a method to generate and manipulate the surface spin current in topological insulators.

Transferring spin-oriented electrons (Linkoping)

The researchers used a combination of a topological insulator (Bismuth Telluride, Bi2Te3) and a regular GaAs semiconductor. The electrons were generated with the same spin in the GaAs using polarized light. The electrons were then transferred to the TI.

Researchers synthesize a new 2D topological insulator

Researchers from Berkeley Lab and UC Berkeley synthesized a new 2D topological insulator material, called 1T’-WTe2. In such a material the flow of electrons is completely linked to the direction of their spin, and is limited to the edge of the material.

Berkeley Labs ALS 1T-WTe2 image

This material excites the scientists as they see great spintronics applications of 2D topological insulators. The researchers now aim to synthesize larger samples and find out the way to selectively adjust and emphasize particular characteristics

Topological insulators can be used to create "spin batteries"

Researchers from Purdue University have demonstrated how topological insulators can be used to create rechargeable "spin batteries". The demonstration showed how spin momentum locking can retain the spin even after two days without current.

Persistent spin polarization measurement

Spin momentum locking is an effect in topological insulators in which the spin of the electrons on the edge of the material change their spin when current is applied.

C-SPIN researchers discuss topological insulators

The University of Minnesota (UMN) published yet another video, interviewing several researchers at the Center for Spintronic Materials, Interfaces, and Novel Architectures (C-SPIN). The topic this time is topological insulators - priming new class of materials.

Topological insulators are materials in which the edges are conductive but the rest of the material acts like an insulator).