Electron superhighways could hold key to quantum computing

A group of researchers has claimed the world is another step closer to building a working quantum computer.

They reckon they might have cracked one of the main components of a working quantum processor, a tiny device which functions as a ‘superhighway’ for electrons.

The team at Rice University developed a quantum spin Hall topological insulator that will be able to control and create qubits as part of a quantum processor, and store them as data. 

One of the problems that all scientists are trying to overcome in creating qubits is making certain that that the information isn’t lost due to quantum fluctuations, known as fault tolerance.

Although it would only take a quantum processor with 30 qubits to perform around the same amount of calculations as a 1 billion transistor microchip, this is something that scientists have found difficult.

Using topological insulators as the basis of a quantum circuit is expected to help increase fault tolerance – due to each qubit being made from a pair of quantum particles that have a shared identity.

Topological insulators can block electrons from flowing through them, though they can flow around the narrow outer edges.  When attached to a superconductor, this can produce stable pairs of quantum particles called Majorana fermions where the two materials meet, meaning there is the potential to generate qubits.

The problem is that these Majorana fermion stable particles have yet to be observed by physicists, so quantum computers are not exactly within reach just yet.

But the team say that they are “well positioned” for more tests, and hope to find out whether the discovery of Majorana fermions will produce stable qubits.