Researchers from the NIST in the US and the University of Tokyo have discovered a metallic antiferromagnet (Mn₃Sn) that exhibits a large magneto-optic Kerr (MOKE) effect, despite a vanishingly small net magnetization at room temperature.

Compared to ferromagnetic materials, metallic antiferromagnets allow for faster dynamics and more densely packed spintronic devices due to the weak interactions between antiferromagnetic cells. The researchers believe that such materials hold promise for future antiferromagnetic spintronic devices, where the magnetic state could transduced optically and switched either optically or by applying current.

Reseaerchers from TU Delft developed a method to convert the spin information into light signals at room temperature. The researchers hope that this method could enable opto-spintronics devices.

The researchers used a device made from a thin silver thread and a 2D tungsten disulfide film on top. Using circularly polarised light, the researchers created excitons with a specific rotational direction (that could be intitialized using the rotational direction of the laser light). The excitons emit photons when they relax. And the emitted light contains the spin information.

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

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.