A team at the University of Sydney (USyd) working with Microsoft, alongside Stanford University in the US, has announced the development of a miniaturised component touted as essential for the scale-up of quantum computing. According to the university, the work represents the first practical application of a new phase of matter that was first discovered in 2006, "topological insulators", which are materials that operate as insulators in the bulk of their structures, but have surfaces that act as conductors. "Manipulation of these materials provide a pathway to construct the circuitry needed for the interaction between quantum and classical systems," explained USyd in a statement. As a result, USyd said they are vital for building a practical quantum computer. The Sydney team developed a microwave circulator, which acts like a traffic roundabout by ensuring that electrical signals only propagate in one direction, clockwise or anti-clockwise, as required.