Research teams from UNSW are investigating multiple pathways to scale up atom-based computing architectures using spin-orbit coupling – advancing towards their goal of building a silicon-based quantum computer in Australia.

Australian scientists have investigated new directions to scale up qubits utilising their spin-orbit coupling, adding a new suite of tools to the armory.

Spin-orbit coupling, the coupling of the qubits’ orbital and spin degree of freedom, allows the manipulation of the qubit via electric, rather than magnetic fields. Using the electric dipole coupling between qubits means they can be placed further apart, thereby providing flexibility in the chip fabrication process.

In one of these approaches, published in Science Advances, a team of scientists led by UNSW Professor Sven Rogge investigated the spin-orbit coupling of a boron atom in silicon.

“Single boron atoms in silicon are a relatively unexplored quantum system, but our research has shown that spin-orbit coupling provides many advantages for scaling up to a large number of qubits in quantum computing,” says Professor Rogge, Program Manager at the Centre for Quantum Computation and Communication Technology (CQC2T).

Artist’s impression of spin-orbit coupling of atom qubits. Illustration: Tony Melov. Credit: CQC2T.