Current flowing along the edges of a promising quantum device is insensitive to its magnetic impurities
Friday, September 30, 2011 - 09:30
in Physics & Chemistry
Conductors of electrical current, including copper, heat up and limit the ability to increase circuit densities. Unusual materials that exhibit the so-called quantum spin Hall effect, in which current can flow without dissipating heat, could provide an alternative to conventional metals. However, internal imperfections, such as magnetic impurities, were assumed to disrupt current flow. Now, using theoretical calculations, a research team from Japan and the US has shown that devices built from these alternative materials are surprisingly immune to the presence of magnetic impurities.