Scientists of the University of Duke in the United States showed that quantum computers as the sum of parts can be more reliable than parts from which they consist. The results published in the article by Nature magazine will help create more error-resistant devices of quantum calculations, which still exist.
In the experiment, the researchers combined several qubs, so that they function as a whole, that is, they formed a logical qubit. To do this, they used error correction code that allows you to get rid of noise affecting calculations. In logical qubit, one qubit contains the necessary information, and the rest allow you to correct errors affecting the accuracy of calculations.
Created by scientists. Logical qubit turned out to be more reliable than the most affected by the erroneous stage necessary for its creation. The team managed to successfully translate logical qubit into its initial state and measure it in 99.4 percent cases, despite the fact that they relied on six quantum operations, which are expected separately to work only in 98.9 percent cases. Thus, in the experiment, imperfect parts work together to minimize the likelihood of serious quantum errors.
Results were achieved using the ion trap system, which uses up to 32 separate ions, which are cooled with a laser and suspended above the electrodes on the chip. Each ion serves as a qubit over which manipulations are carried out with lasers. Successfully creating a fault-tolerant logical qubit, the researchers showed that a cautious approach can free quantum calculations from inevitable errors.