Physicists at the University of Oxford have achieved a new world record in controlling a single quantum bit, nearly seven times greater than previous records. The experiment reported in Physical Review Letters shows that errors occur just 0.000015% of the time or one error in six million operations.
To put this into perspective, an error is more likely to happen than a person getting struck by lightning (1 in 1.2 million). Quantum bits are prone to errors due to their noisy nature, but this breakthrough brings physicists closer to creating reliable quantum computers.
The Oxford team used microwaves instead of lasers to control the quantum state of the trapped calcium ion qubit, offering greater control and a more robust setup. This achievement demonstrates precise control over qubits, which is essential for other quantum technologies like clocks and sensors.
However, this experiment is still a long way from practical quantum computing. A single qubit is not enough; hundreds or millions of qubits will be needed to work together in tandem, increasing the quantum noise that leads to errors. The current record for a 2-qubit logic gate is one error every 2,000 operations, highlighting the significant progress still needed.
Despite this, this breakthrough marks an important step towards building practical quantum computers with low error rates. “As far as we are aware, this is the most accurate qubit operation ever recorded,” says co-author David Lucas. The Oxford team’s achievement demonstrates a major step forward in reducing errors and opening the way for future quantum computers to be smaller, faster, and more efficient.
Source: https://cosmosmagazine.com/technology/computing/quantum-bit-contol-record