Quantum Computing Reaches Important Milestone: Accuracy 99% | Quantum computer | Spin | Silicon quantum processor

Bit, also known as bit, is the basic unit of information in a computer. At present, computers have only two states, 0 and 1; AndQuantum computerIn addition to 0 and 1, there is a third state of quantum bits, 0 and 1, which is called the quantum superposition state. This allows quantum computers to gain more computing power than today’s computers. But because quantum superposition conditions are easily disturbed by external factors, qubits have a higher error rate. This is a major obstacle on the path to quantum computer development.

All three studies have made progress in this regard. In addition, all three studies are designed using silicon, which means that the devices are more compatible with current mainstream semiconductor fabrication techniques.

Phosphorus nucleus was used in the first study conducted by physicist Andrea Morello at the University of New South Wales (UNSW) in Australia.RotateProperties encode quantum information.

The other two studies, conducted by Delft University of Technology in the Netherlands and Reiken in Japan, used a different technique – quantum trapped in silicon and silicon-germanium alloys within the point.RotateElectrons in quantum bits. Single-digit and double-digit systems designed by two research groupsAccuracyThey all exceeded 99% as shown in the table below.

In 2014, Morello said, their silicon-based cubits could hold up to 35 seconds of data, compared to 100 microseconds for other technologies of the time. But in order to achieve this, their qubits need to be isolated from the surrounding environment, which leads to poor communication between the bits. In order to achieve large-scale operations, quantum bits must be able to communicate smoothly.

Now they have solved this problem. They used a three-qubit system consisting of one electron and two phosphorus nuclei. Two phosphorus nuclei communicate through these electrons, and the researchers handle only two phosphorus nuclei, so this system has only two quantum numbers involved, but it is a system of three quantum numbers.

Seigo Tharucha, head of the Dutch research group, said: “This is the first time that spin quantum digital technology has competed with superconducting circuits and ion trap technologies based on global quantum control performance.”

Morello said: “The use of error correction protocols is only possible if the error rate is less than 1%. Now that this standard has finally been reached, the next step is to start designing.Silicon quantum processor, Scale up to perform meaningful and reliable actions. ”◇ #

Responsible Editor: Ye Ziwei