A group of researchers in Japan and China identified the requirements for the development of new types of extremely low power consumption electric devices by studying Cr-doped (Sb, Bi)2Te3 thin films. This study has been reported in Nature Communications.
At extremely low temperatures, an electric current flows around the edge of the film without energy loss, and under no external magnetic field.
Ref: Carrier-mediated ferromagnetism in the magnetic topological insulator Cr-doped (Sb,Bi)2Te3. Nature Communications (19 November 2015) | DOI: 10.1038/ncomms9913