Above -A silicon qubit high-frequency measurement stage, which is positioned inside a dilution refrigerator to cool the chip to around 0.1 degrees above absolute zero. Picture: UNSW/Ken Leanfore

UNSW Sydney have created artificial atoms in silicon chips that offer improved stability for quantum computing.

In a paper published today in Nature Communications, UNSW quantum computing researchers describe how they created artificial atoms in a silicon 'quantum dot', a tiny space in a quantum circuit where electrons are used as qubits (or quantum bits), the basic units of quantum information.

The results experimentally demonstrate that robust spin qubits can be implemented in multielectron quantum dots up to at least the third valence shell. Their utility indicates that it is not necessary to operate quantum dot qubits at single-electron occupancy, where disorder can degrade their reliability and performance. Furthermore, the larger size of multielectron wavefunctions combined with EDSR can enable higher control fidelities, and should also enhance exchange coupling between qubit.