Error-Correcting Quantum ComputersBy Cinthya Alaniz Salazar | Thu, 10/07/2021 - 09:59
Quantum computing currently generates too many errors for pragmatic applications. However, the combined application of multiple qubits has increased the time of sustained calculations these computers can handle. Addressing this obstacle may provide a shorter route to feasible commercial applications which is projected to revolutionize multiple industries.
Conventional computers store information as ones or zeros and perform calculations using electronic data-processing components called transistors. Quantum computers’ qubits, on the other hand, have the capacity to store combinations of ones and zeros as a single unit, which is the result of a quantum physics phenomenon called superposition. Qubits can be interlinked by entanglement, which would give these computers the ability to harness quantum mechanics.
"We're in the early industrial era of quantum computing," said Seth Lloyd, an MIT professor who helped found the field in the 1990s. He says the "huge advances" in the area are comparable to the early use of steam engines in trains, ships and factories, boosting production capacity.
Breakthrough research published in Nature, a global scientific journal, found that the combined power of nine qubits, called a logical qubit, can solve quantum computer’s high error rate. Moreover, unlike individual qubits, the information is stored redundantly which allows researchers to probe and identity mistakes. “If a piece goes missing, you can reconstruct it from the other pieces, like Voldemort,” says observing quantum physicist David Schuster of the University of Chicago.
To make this logical qubit, researchers used a technique called Bacon-Shor code which traps qubits made of ytterbium ions inside a chip vacuum, which are manipulated with lasers. Researchers also developed sequences of operations so that errors do not multiply uncontrollably, which is called “fault tolerance.” According to quantum physicist Christopher Monroe, of the University of Maryland, this added effort helped the new logical qubit have a lower error rate than that of the most flawed components that made it up.
“This is a key demonstration on the path to build a large-scale quantum computer,” says quantum physicist Winfried Hensinger of the University of Sussex in Brighton, England. Yet, that path remains a long one, he reflects. For these computers to conduct complex calculations, scientists will have to dramatically scale up the number of qubits in the machines. Now that scientists have proven that errors can be kept under control, he says, “there’s nothing fundamentally stopping us to build a useful quantum computer.”
While the scientific community anxiously awaits for this technology to become part of the mainstream, Salvador Venegas, Founder of Quantum Computing in Mexico, is already developing a blockchain protocol to protect against foreseeable quantum computer attacks. “When quantum computers reach a sufficient size, Shor’s Algorithm will make cryptographic protocols vulnerable,” Venegas said in an article for Tecnológico de Monterrey’s site, Conecta. “Blockchain is a technological paradigm that Will impact many áreas where there is data Exchange and that information needs to be stored safely.”