Fractionally charged: An illustration of the experimental set-up with extremely pure gallium arsenide. Quasiparticles, shown in yellow, travel along the edge and have one quarter the charge of an electron.
Credit: Genia Brodsky, Weizmann Institute.
Robust qubits
All computing is based on strings of bits, where a bit can take the value 1 or 0. Currently, this is done by transistors. But in a quantum computer (see, Seeking a quantum computing breakthrough, Cosmos Online), the bits would be made from particles that are linked together by quantum behaviour. These are termed 'qubits' or quantum bits. In topological quantum computers a bit could be made from two quasiparticles.
In other types of quantum computing, for example linking quantum bits with lasers, the system is strongly affected by its environment. An ever-so-slight movement stops the system from working. But because of the path of these quasiparticles is not important, a topological quantum computer would be much more robust.
"The possibility of producing a topologically based quantum computer based on these quasiparticles is interesting," commented physicist Jeff McCallum, from the University of Melbourne. "[But] there is plenty of room for more competitors in the quantum computer race and there is no clear winner in the field yet."
Scientists predict the first quantum computer may be here in less than 20 years and would be many times more powerful than modern supercomputers, rapidly solving problems that would otherwise take many years to complete.
