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 electroncs were generated with the same spin in the GaAs using polarized light. The electrons were then transferred to the TI.
The whole demonstration was performed without any external electric voltage - only using light energy. This could pave the way to novel opto-spintronics devices.