A group of physicists from Oxford University has accomplished the lowest error rate (just 0.000015%, or one error in 6.7 million operations) in quantum logic operations.

“As far as we know, this is the most accurate qubit manipulation ever reported globally,” stated Professor David Lucas from Oxford University.

“This represents a crucial milestone in constructing a practical quantum computer capable of solving real-world problems.”

To conduct meaningful calculations on quantum computers, millions of operations must engage numerous qubits.

Consequently, if the error rate is excessively high, the end result of the computation becomes useless.

Error correction techniques can address mistakes, but they require additional qubits, which come at a cost.

By minimizing errors, new methodologies decrease the number of qubits needed, leading to a reduction in both the cost and size of the quantum computer itself.

“By significantly decreasing the chances of errors, this advancement will greatly lessen the infrastructure necessary for error correction, paving the way for future quantum computers to be smaller, faster, and more efficient,” said Molly Smith, a graduate student at Oxford University.

“Kitz’s precise control is beneficial for other quantum technologies, including timepieces and quantum sensors.”

This groundbreaking accuracy was attained using trapped calcium ions as qubits.

These ions are ideal candidates for storing quantum information due to their longevity and resilience.

Researchers adopted an alternative method, using electron (microwave) signals to manage the quantum states of calcium ions instead of traditional lasers.

This technique is more stable than laser control and offers several advantages for constructing practical quantum computers.

For instance, electronic control is less expensive and more robust than lasers, facilitating easier integration into ion trap chips.

Moreover, the experiment was conducted at room temperature and without magnetic shielding, simplifying the technical necessities of operating quantum computers.

“This record-setting achievement signifies a significant milestone, but it is part of a larger challenge,” the author remarked.

“In quantum computing, both single and two-qubit gates must function together.”

“Currently, the gates of the two-qubit systems still experience a very high error rate, approximately 1 in 2,000 even in the best demonstration to date.

Their paper has been published online in the journal Physical Review Letters.

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MC Smith et al. 2025. Single qubit gate with errors at the 10^-7 level. Phys. Rev. Lett, in press; doi: 10.1103/42w2-6ccy