A research team from Xanadu in Canada and the National Institute of Standards and Technology in the United States claims that their quantum computer Borealis has gained a computational advantage in solving the problem of sampling bosons. In an article published in the journal Nature, the group describes their computer and how well it works. Daniel Jost Brod of Fluminense University in Brazil published an article in the same issue of the journal titled “News and Thoughts”, giving a brief history of quantum computing and the team’s work on this new project.

As work continues to create a truly usable quantum computer, research teams are adding more power to the devices they’re working on and then testing them for computational advantages. Such tests are designed to demonstrate that this device can solve a task that requires traditional computers to take too long to be practical.

In this new study, the researchers took a sample of bosons using a photon machine that uses photons to represent qubits. Technically called the Gaussian boson sampling task, this task involves preparing light states and directing them through a network of luminaires, then counting the number of photons that reach the detector. While the best modern computers are fast-connecting trying to solve this problem, theory suggests a quantum computer should shine. Previous attempts to address this problem have involved the use of 76 to 113 photons. The machine created by the team for this new study was able to reach 219 photons, an average of 125 – a significant step forward.

During the mission, the team found that Borealis was able to complete the mission in 36 microseconds. Researchers estimate that it would take about 9,000 years for the best conventional computer to complete the same task. This difference shows a computational advantage, according to the researchers. The researchers took a further step in their study, checking the result given by Borealis and showing that it cannot be falsified, indicating that the answers it gave were correct. Source