China has developed the world's first ultra-fast memory for quantum computers, a sector it has declared it will nurture as a future industry over the next five years. The achievement marks a clue to solving, at the experimental level, the "data-reading bottleneck" that has long been a chronic challenge for quantum computers. With this, China has taken a first step toward resolving one of the core obstacles to commercializing big-data applications such as drug discovery and financial fraud detection. As China competes with the United States for technological supremacy, attention is focused on whether it can secure leadership in next-generation core technologies.
According to the South China Morning Post (SCMP) on Wednesday, a research team led by Zhejiang University published a paper in the March issue of the journal Nature Physics stating that it had implemented a "quantum random access memory (QRAM)" structure in a superconducting quantum processor. QRAM is a core component that allows quantum computers to efficiently access existing data. It is also a prerequisite for many quantum algorithms to achieve "quantum speed." However, QRAM is a different concept from quantum memory. While quantum memory stores qubits themselves, QRAM is a technology that loads data in the form of 0s and 1s found in conventional computers all at once so that quantum computers can read it in a quantum manner (superposition state).
Quantum computers use qubits, which represent 0 and 1 simultaneously, to solve complex problems at speeds impossible for conventional supercomputers. With computing power that surpasses existing supercomputers under certain conditions, they are regarded as a key pillar of next-generation industrial innovation, including drug discovery, code-breaking, and the search for new materials. However, when processing vast amounts of conventional data sequentially, even the fastest quantum computer slows down. While theoretical research on QRAM has continued, this is the first actual experimental implementation.
Lu Lichang, an assistant professor at Zhejiang University's College of Computer Science and Technology and a co-author of the paper, said in a May interview with the state-run Science and Technology Daily, "We have succeeded for the first time in operating a QRAM prototype that can access 4-bit and 8-bit data on a superconducting quantum chip," adding, "We have proven that QRAM can process multiple data inputs simultaneously."
China's successful demonstration of QRAM development holds great industrial significance. While the United States still leads in core quantum research fields, China is catching up by pushing a centralized industrial strategy. In its 15th Five-Year Plan announced in March, the Chinese government designated quantum technology as one of seven future industries, elevating it to a key national task. In response, the US Department of Commerce decided on the 21st of last month to provide a total of $2.013 billion (about 3 trillion won) to nine quantum computing companies, including IBM, based on the CHIPS Act.
If this technology is commercialized, it could greatly shorten the drug development cycle in pharmaceuticals by rapidly extracting the topological properties of molecules from chemical databases numbering in the hundreds of millions. In finance, it is expected to be used to detect fraud by analyzing vast transaction records. In the AI field, it could maximize the processing power of quantum AI in large-scale big-data tasks such as natural language processing and image recognition.
However, considerable time appears to be needed before QRAM can be commercialized in practice. The 4-bit and 8-bit demonstration is effectively at the proof-of-concept level, and to be used for drug discovery or financial fraud detection, it must be able to process millions to hundreds of millions of bits. Accuracy must also be raised from the current level of about 60% to over 99%. In addition, challenges such as error correction, qubit scaling, and room-temperature operation remain to be solved. In particular, QRAM is merely research at the interface level, one of many layers in the quantum computing ecosystem. The academic consensus is that at least 10 years will be needed to extend this to the algorithm and application stages, as well as the hardware led by IBM.
Lu stressed, "Current quantum algorithms are theoretically impressive, but to run them on quantum computers, they must efficiently access vast amounts of conventional data," adding, "Without QRAM, many application fields will inevitably remain pure theory."
Meanwhile, according to Chinese research institutions, the global quantum technology market in 2024 was estimated at about $8 billion (about 12.3 trillion won), of which China's share stood at about 25%.
