Since quantum supremacy was achieved in 2019, you can regularly hear about quantum computers containing more and more qubits, but the technology is still far from practical use, for example, for decryption last year. However, Microsoft's announcement on Wednesday may change that, as the company claims to have created a system that can operate with 800 times fewer errors than before. On the company blog.
In classical computers, the basic unit of information is the bit, which has two possible values, but quantum computers work with qubits, which can be in both states at the same time, using the phenomenon of superposition in quantum mechanics – more about this in more detail. You can read it by clicking here. Meanwhile, qubits are not always accurate, so quantum computers operate with a very high error rate when reading them, so they cannot be used in practice.
Microsoft has now solved this problem by creating so-called logical qubits from several physical qubits, with which it has been able to significantly reduce the number of errors. Specifically, they reported an 800-fold improvement, and also confirmed that they were able to run 14,000 experiments without getting a single error in the trapped ion machine at Quantinuum, which collaborated with them on the project. Creating logical qubits naturally reduces the number of qubits that can be used in calculations, but according to Microsoft, it is how fault-tolerant the system is that matters most.
Jason Zander, Microsoft's executive vice president, wrote in the post that with Microsoft's breakthrough in quantum computing technology, it has been possible to advance to the level of quantum computers where they can actually be used in practice. Of course, this is far from the end, as logical qubits must be maintained in a stable state for as long as possible, as we will run more and more complex applications on them. This requires increasing the quantity and/or stability of physical qubits.
The next level will be where quantum computers will be truly scalable and programmable. In theory, solving the most complex problems facing humanity would not be impossible with these things, and according to Microsoft, we could benefit from them in particular in chemistry and materials science. It is still not possible to know when we can reach this level, but the company confirmed that it is spending a lot of money on this matter. Azure Quantum Elements users will be able to start playing with the just-introduced logical qubits in the coming months.
