Physicists Extend Qubit Lifespan In Pivotal Validation of Quantum Computing

An anonymous reader quotes a report from ScienceAlert: Keeping enough qubits in their ideal state long enough for computations has so far proved a challenge. In a new experiment, scientists were able to keep a qubit in that state for twice as long as normal. Along the way, they demonstrated the practicality of quantum error correction (QEC), a process that keeps quantum information intact for longer by introducing room for redundancy and error removal. The idea of QEC has been around since the mid-90s, but it’s now been shown to work in real time. Part of the reason for the experiment’s success was the introduction of machine learning AI algorithms to tweak the error correction routine. “For the first time, we have shown that making the system more redundant and actively detecting and correcting quantum errors provided a gain in the resilience of quantum information,” says physicist Michel Devoret, from Yale University in Connecticut. […] Like many quantum physics experiments, this one was run at ultra-cold temperatures — a hundred times colder than outer space, in this case. The setup has to be carefully controlled in order to protect the qubit as much as possible. The error-corrected qubit lasted for 1.8 milliseconds — only a blink as we might experience it, but an impressive span for a qubit operating on the quantum level. Now the research team will be able to refine the process further. “Our experiment shows that quantum error correction is a real practical tool,” says Devoret. “It’s more than just a proof-of-principle demonstration.” In this case the breakthrough was down to several different factors, rather than one change. The QEC code was actually one from 2001, but improvements to it as well as upgrades to the quantum circuit fabrication process made a difference. “Our experiment validates a cornerstone assumption of quantum computing, and this makes me very excited about the future of this field,” says Volodymyr Sivak, a research scientist at Google and formerly at Yale University. The research has been published in Nature. Read more of this story at Slashdot.