2025 is the International Year of Quantum Science and Technology; experts explain how quantum computers work and what advances are expected

The United Nations has designated 2025 as the International Year of Quantum Science and Technology (IYQ) to raise public awareness of quantum science and its applications. A quantum systems researcher explains what quantum chips are needed for quantum computers and how much quantum computers will develop from 2025 onwards.

2025 will see huge advances in quantum computing. So what is a quantum chip and how does it work?
https://theconversation.com/2025-will-see-huge-advances-in-quantum-computing-so-what-is-a-quantum-chip-and-how-does-it-work-246336

Quantum computers are computers that use quantum mechanics in their calculations and are expected to perform large-scale calculations that are impossible with conventional computers (classical computers). Conventional computers process information in the form of binary numbers that represent either '0' or '1'. On the other hand, quantum bits , the basic units of quantum chips, represent 'superposition states' that probabilistically represent 0 and 1, and because the basic units can represent more patterns, quantum processors can store or process vast amounts of data at much faster speeds than conventional computers.

What on earth is going on inside a quantum computer? - GIGAZINE

Muhammad Usman, principal research scientist at the Quantum Systems Division of the Commonwealth Scientific and Industrial Research Organization of Australia, explains how to realize quantum bits and how to utilize quantum computing. According to Usman, quantum bits have quality, and even if a quantum chip contains thousands of quantum bits, if the quantum bits are of low quality, the quantum chip will not be able to perform useful computational tasks.

There are various approaches to creating quantum bits, including superconducting devices, semiconductors, and photonics. Each method has its advantages and disadvantages, and quantum bits are highly sensitive and susceptible to various factors, such as temperature changes, problems with control signals, and imperfections in the manufacturing process. A quantum bit that is prone to errors reduces its reliability, known as 'fidelity.' Therefore, a 'logical quantum bit' has been designed that retains information without being affected by the loss of fidelity by extracting the error information and restoring the information.

In December 2024, Google announced the quantum chip 'Willow' equipped with 105 qubits to achieve ultra-fast calculations and improved quantum error correction. According to a paper published in Nature by Google Quantum AI Lab, Google's quantum computing research division, the error rate was reduced by almost half at each step of expanding the qubit array from the smallest array, starting with 3 × 3, then 5 × 5, and then 7 × 7. In addition, Microsoft also announced in September 2024 that it had succeeded in creating 12 high-fidelity logical qubits, and results have been seen that solve the vulnerability of qubits and approach the practical use of quantum computers.

Google announces 'Willow', a quantum chip that can perform calculations that would take 10^25 years on a supercomputer in just 5 minutes - GIGAZINE

Google reported that 'Willow could perform calculations that would take ^10-25 years using the fastest supercomputer as of the end of 2024 in less than five minutes,' and Chinese researchers announced that quantum computers could decrypt the RSA encryption , a cryptography whose security is based on the difficulty of prime factorization. If a fully functional quantum processor is realized, it could have a revolutionary impact not only on research and technology, but also on many other fields such as the economy, by discovering new correlations in clinical trial data and genetics that conventional computers could not process, and by significantly improving the safety of various systems that use AI algorithms, such as autonomous vehicles and banking.

According to Usman, it will take several years to realize a quantum chip that can integrate multiple logical qubits, operate coherently, and solve real-world problems. In fact, Microsoft, which announced that it has created 12 logical qubits, aims to develop a 'quantum computer system that can create 100 reliable logical qubits' that can be expected to achieve scientific results by 2029, and it is necessary to have another 1,000 logical qubits to be able to expect commercial results.

While quantum processors are advancing rapidly, research and development in the areas of software and algorithms is also attracting attention. Usman said, 'Quantum chips will continue to scale up in the next few years. And as the hardware part develops with quantum processors, quantum algorithms will be further developed and tested. Building a full-scale quantum computer is a difficult task because it requires simultaneous progress in many areas, including expanding the number of qubits on the chip, improving fidelity, improving error correction, software, algorithms, computing, and more. After many years of great fundamental research, we can expect new breakthroughs in all of the above by 2025.'