Lei Feng, whether it’s government agencies and university institutions around the world, or tech giants like IBM and Google, is trying to answer the question of quantum computing: How will quantum computers realize their enormous potential if reliable results are not delivered continuously?
From many perspectives, mechanical vulnerability, engineering complexity, aseptic and low-temperature environments are potential factors that cause errors in quantum computing, and the most critical factor is quantum bit flips, which are highly likely.
However, before creating a truly useful universal quantum computer, minimizing the errors of quantum computers is the biggest challenge facing scientists today.
To ensure that quantum computers function and output results before “downtime” or quantum de-generation due to errors, many scientists and engineers claim to have found a way to detect and correct these errors. Among them, a solution called “surface code” has attracted much attention.
Lei Feng network learned that the surface code has advantages in robustness, and it is very suitable for two-dimensional environment (such as chips). What’s more, in the event of quantum entanglement, it can help a single qubit to share information with other qubits of the same lattice. That is, when measuring a qubit, the surface code shows the error between adjacent qubits.
To have quantum computers handle complex tasks, error-correcting code must be able to execute quantum doors — the most basic logical operation of quantum bit information, which can be combined to run algorithms. Physicists have described two quantum gate calculations (distinguished by different mathematical methods) necessary to achieve universal quantum computing, one of which is the Clifford gate, which can only be used in conjunction with magic distillation techniques, a non-Clifford door operation using a variety of noisy quantum states.
Benjamin Brown, a researcher at the University of Sydney’s School of Physics, said:
Without magic distillation or similar technology, quantum computers are like computers without division buttons, and their function is limited. However, the combination of Clifford doors and non-Clifford doors can be resource-intensive and may result in quantum computers not being resource-intensive enough to handle other tasks.
因此，Benjamin Brown 开发了一种新型的非 Clifford 门的纠错方法，从而大大减轻了蒸馏的负担。这个方法就涉及到上文所提到的表面代码，只不过，Benjamin Brown 对二维的表面代码进行了优化，让它可以适用于三维环境，时间是第三维度。这一研究已经发表在了《Sience Advance》上。
Benjamin Brown says the study has proved theoretically and mathematically feasible, followed by simulated code and looking at the results in practice.
Michael Beverland, a research institute at Microsoft’s Quantum Research Laboratory, also commented on the study:
Benjamin Brown 探索了一种奇妙的方式来对量子计算进行纠错。该研究是振奋人心的，毕竟许多研究人员认为这些是不可能的实现的。