Google takes new step towards quantum computerBack
Google is one step closer to building a fully functioning quantum computer. Researchers at Google Quantum AI have made progress in correcting errors that affect the system, decreasing error rates as the system grows in size. According to Google, this is a major step towards using quantum computers for practical applications.
Quantum computers are seen as the future of computer science. They are able to perform calculations that are impossible on the 'classic' computers we use today, but they are also prone to errors. Now Google researchers say they've found a way to correct errors by making the quantum code bigger.
According to Google, this is the second step of a total of six that are needed to come to a working quantum computer. The first step took place in 2019 when a Google quantum computer performed a calculation that would have taken thousands of years on an ordinary computer.
All computers are subject to failure due to stray electrons crossing a barrier or a cosmic ray particle disrupting the circuit. An ordinary computer chip copies part of the information into 'error correction' bits. If an error occurs, the chip can automatically detect and solve the problem.
In quantum information this is not possible without the quantum state (qubits, which can simultaneously have the value 0 and 1) being irretrievably lost; information cannot simply be copied. Google's researchers solved this by using a collection of physical qubits instead of a single one. The computer then uses some of these physical qubits to correct any errors. The more physical qubits there are, the better they can correct an error. A version with 49 qubits was even able to recover from two simultaneous errors.
But there must be enough capacity left to perform calculations, and the Google team is still a long way off. So Step Six is a machine with a million physical qubits, encoding 1000 logical qubits. And that is still a long way to go.