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Topological insulators(TI): A new revolution to faster electronics

 State University report they have created a TI film just 25 atoms thick that adheres to an insulating magnetic film, creating a "heterostructure." This heterostructure makes TI surfaces magnetic at room temperatures and higher, to above 400 Kelvin or more than 720 degrees Fahrenheit.
The surfaces of TI are only a few atoms thick and need little power to conduct electricity. If TI surfaces are made magnetic, current only flows along the edges of the devices, requiring even less energy. Thanks to this so-called quantum anomalous Hall effect, or QAHE, a TI device could be tiny and its batteries long lasting, Shi said.
Engineers love QAHE because it makes devices very robust, that is, hearty enough to stand up against defects or errors, so that a faulty application, for instance, doesn't crash an entire operating system.
Topological insulators are the only materials right now that can achieve the coveted QAHE, but only after they are magnetized, and therein lies the problem: TI surfaces aren't naturally magnetic.
Scientists have been able to achieve magnetism in TI by doping, i.e. introducing magnetic impurities to the material, which also made it less stable, Shi said. The doping allowed TI surfaces to demonstrate QAHE, but only at extremely low temperatures -- a few hundredths of a degree in Kelvin above absolute zero, or about 459 degrees below zero Fahrenheit -- not exactly conducive to wide popular use.
Source
  1. Chi Tang, Cui-Zu Chang, Gejian Zhao, Yawen Liu, Zilong Jiang, Chao-Xing Liu, Martha R. Mccartney, David J. Smith, Tingyong Chen, Jagadeesh S. Moodera, and Jing Shi. Above 400-K robust perpendicular ferromagnetic phase in a topological insulator. Science Advances, 23 Jun 2017 DOI: 10.1126/sciadv.1700307

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