One of Canada’s quantum frontrunners announced another breakthrough in error correction on quantum computers, in an effort to make them useful in the real world.
The news: Sherbrooke, Que.-based Nord Quantique, last valued at $1.4 billion USD ($1.9 billion CAD), published a research paper demonstrating that it achieved errors below 0.1 percent on a single-mode, grid-state qubit. This means it significantly reduced the number of errors and interference that could cause the basic hardware unit of quantum computing to fail—bringing the company’s platform up to speed with hardware used by top companies like IBM and Google.
From the source: “Every quantum computer has to do two things around the actual calculation: set the qubits to the correct starting state and read out an accurate answer at the end,” Nord Quantique CEO Julien Camirand Lemyre explained in an email to BetaKit. “If either of those is incorrect, it doesn’t matter how good everything in the middle is, the result is unreliable.”
Following the thread: Error correction is one of the toughest engineering challenges facing quantum computing—without it, the machines can still make mistakes. Physical qubits are very sensitive to external factors like noise and temperature, so error correction prevents them from falling into decoherence (losing their quantum properties, and their functionality).
With its superconducting qubits, Nord Quantique has been working on eliminating “bookend” errors—mistakes at the starting state and the final answer. Nord Quantique says its latest advancement, building on other error-correction milestones, has gotten these types of errors to occur less than 0.1 percent of the time. Lemyre added that the team tackled this problem without bolting on extra hardware, thus avoiding any additional costs.
Final thought: With useful quantum computers still years away, competition in the quantum industry has looked more like a research and development battle. Different terms for technological breakthroughs—such as quantum supremacy or quantum advantage—have emerged to distinguish big advancements from small steps forward, and scientists have sparred over whether companies like Microsoft and D-Wave are using them correctly. Lemyre said that Nord Quantique’s news may not be “flashy,” but it’s the type of “unglamorous fix” that must occur before fault-tolerant quantum computing can become a reality.
Feature image courtesy Nord Quantique.