The company’s recent research may signal a step toward overcoming one obstacle to technology
Google claims to have overcome the quantum computer errors. This is a significant breakthrough that could lead to revolutionary computing.
Hartmut Neven, the head of Google’s quant efforts, said that the internet company’s findings have been published in Nature. They are a “milestone” on their journey to create a useful quantum computing device. Hartmut Neven described error correction as “a necessary rite-of-passage that every quantum computing technology must go through”.
Quantum computers are not able to produce useful results due to the fact that quantum bits (or qubits) they use only hold their quantum states for a fraction of a second. Information encoded in quantum systems is lost before it can finish its calculations. This is the most difficult technical challenge facing the industry.
Many quantum start-ups are focusing their efforts on programming today’s error-prone or “noisy” machines. Even if this results in a slight improvement over traditional computers, some of these companies have placed great hopes for the future. But, these efforts have not yielded concrete results. This has led to the growing belief that quantum computing won’t be useful until the much bigger problem of error correction is solved.
Google researchers claimed that they have found a way to distribute the quantum computer’s information across many qubits. This allows the whole system to retain enough information to perform a calculation even if individual qubits are removed from their quantum states.
Nature published research that showed a 4 percent reduction in error rates. This was because Google increased its technology to run on a larger quantum computer. Researchers said that this was the first time that an increase in computer size has not led to an increase in error rates. Neven stated that Google had reached a “breakeven point”, after which more improvements would lead to steady gains in performance. This put the company on the path to a practical quantum computer.
According to Julian Kelly (Google researcher), the breakthrough in error correction was due to improvements Google made to all components its quantum computer. These included the quality of its qubits, its control software, and the cryogenic equipment that chilled the computer to nearly absolute zero. He said that this had allowed the system to be scaled up without causing an exponential increase in error rates.
Google said that the breakthrough was only one of six steps needed to create a practical quantum computer. Next, it needed to perfect its engineering so that it could create a “logical qubit” — an abstraction built on top the imperfect physical qubits that can work without errors. Neven stated that Google believes it will be a useful machine when it has figured out how to link 1000 logical qubits together into one system.
Google’s claims about quantum computing research have been controversial in the past. It claimed that it had reached quantum supremacy in a Nature article. This is the point at which a quantum computing machine can perform calculations that are impossible to do on a traditional computer.
But, this assertion was challengedby IBM and other organizations, and new programming methods were developed to improve the performance of traditional computers. This pushed back the time when quantum machine makers could claim to have achieved “supremacy”.
Google researchers stated in this week’s Nature paper that they are being cautious about their latest breakthrough. Their error-correction method could not be applied to larger quantum systems in the future, they warned.