High-fidelity sequential readout of two electron spins. Credit: Watson et al

Scaling up quantum computers remains one of the toughest challenges facing quantum computing research teams around the world. But new results published in Science Advances show that single-atom qubits in silicon can be engineered with atomic precision to have a five-fold increase in spin relaxation times.

These two-qubit devices are the only semiconductor-based qubits where both qubits have demonstrated the extremely high fidelities required for fault tolerant operation.

The two-qubit readout results were published in Science Advances.