Australian engineers have discovered a new way of precisely controlling single electrons nestled in quantum dots that run logic gates. What’s more, the new mechanism is less bulky and requires fewer parts, which could prove essential to making large-scale silicon quantum computers a reality.
The serendipitous discovery, made by engineers at the quantum computing start-up Diraq and UNSW Sydney, is detailed on January 12 in the journal Nature Nanotechnology.
“This was a completely new effect we’d never seen before, which we didn’t quite understand at first,” said lead author Dr. Will Gilbert, a quantum processor engineer at Diraq, a UNSW spin-off company based at its Sydney campus. “But it quickly became clear that this was a powerful new way of controlling spins in a quantum dot. And that was super exciting.”
Logic gates are the basic building block of all computation; they allow ‘bits’ – or binary digits (0s and 1s) – to work together to process information. However, a quantum bit (or qubit) exists in both of these states at once, a condition known as a ‘superposition’. This allows a multitude of computation strategies – some exponentially faster, some operating simultaneously – that are beyond classical computers. Qubits themselves are made up of ‘quantum dots’, tiny nanodevices which can trap one or a few electrons. Precise control of the electrons is necessary for computation to occur. READ MORE...
