China’s new chip stores data with a single electron, breaking AI memory bottleneck

How many electrons does it take to store a single bit of information? For today’s most advanced dynamic random access memory (DRAM) chips from Samsung and SK Hynix, the answer is roughly 200,000. That is the price of reliability – a vast reservoir of charge needed to ensure a “1” or “0” does not fade into noise. But a team at Fudan University in Shanghai has just collapsed that number to its theoretical floor: one. In a paper published on July 16 in Science, microelectronics professor Zhou Peng and his colleagues detailed a working two-dimensional (2D) flash memory that traps and reads a solitary electron at room temperature – a feat long regarded as the holy grail for semiconductors. The device, which they named Guiyi, lifts a faint, fleeting signal from just tens of millivolts to a robust 0.5 volts, a tenfold improvement over any previous single-electron attempt. For the general public, the most direct impact of this technology is that it makes it possible to run large language models on mobile phones using minimal power, without the artificial intelligence (AI) “losing its memory” during conversations. If a memory device is a “reservoir”, one electron is like a drop of water within it. At the end of the last century, when scientists attempted to store data using a single electron, its signal was too faint. It was like trying to detect the ripples of a single drop of water in a vast reservoir. This made the global scientific community pessimistic about observing and applying single-electron storage. To solve this problem, Zhou’s team altered the structure of the 2D flash chip using the super-thin material graphene. This changed the “reservoir” wall so electrons cannot escape and also amplified their signal so scientists can perceive changes with just a single “drop of water”. Zhou explained that the technique’s name, Guiyi, comes from a Chinese Buddhist phrase: “A tiny mustard seed can hold the massive Mount Sumeru; all great truths converge into one.” The name, meaning “return to one”, is a nod to the ability to store data with a single electron while bringing speed, stability and energy efficiency together in a single design. Additionally, the Guiyi structure revealed and verified two new quantum behaviours: programming voltage quantisation and self-limiting programming. In the future, these behaviours could enable precise reading and writing of what is known as the Nth quantum state, greatly increasing how much information can be stored on a single chip. In an interview with Jiefang Daily last week, Zhou said he planned to set up a company in the second half of this year aimed at commercialising the technology in three to five years. He said in an email that the technology was in the process of entering mass production and would be able to “shake up the existing storage market” now dominated by Samsung and SK Hynix. “There should be some more breakthroughs [this year],” he added. This is not his team’s first major discovery in the field of storage chips. In April last year, they unveiled PoX, the world’s fastest non-volatile storage device. Half a year later, they developed Changying, an atomic chip integration framework that integrates PoX with a silicon-based process platform, achieving the world’s first 2D silicon hybrid flash memory chip. It was selected as one of the top 10 scientific advances in China by the National Natural Science Foundation of China for 2025.