Fudan team develops quantum flash device hitting theoretical one-electron-one-bit storage limit

Storage chips form the fundamental underpinning of computing power, yet latency and power consumption arising from data exchange present fundamental bottlenecks holding back computing performance. Research work unveiled on 17 July features breakthrough quantum flash technology developed by researchers at Fudan University, published in the journal Science.

The team has fabricated a device delivering the world’s largest non-volatile quantum storage window, establishing an original theoretical framework for single-electron quantum storage and filling critical theoretical gaps required for the engineering rollout of quantum memory systems.

In theoretical terms, the principle of one electron encoding one bit marks the physical ceiling for storage density. Contemporary mainstream dynamic random-access memory consumes roughly 200,000 electrons to record a single bit of data.

A storage component can be likened to a reservoir, with electrons acting as individual water droplets within it. Observing single-electron storage resembles detecting the fluctuation of a single droplet inside a vast reservoir. Drawing on fundamental principles of quantum mechanics and leveraging the capacity of atomically thin two-dimensional semiconductors to confine electrons, the group has engineered a quantum flash device named Guiyi. Stable single-electron storage behaviour is observed for the first time at a room temperature of 27 degrees Celsius. The advance overcomes technical barriers seen in comparable experiments, where single-electron states cannot remain stable at ambient temperatures and quantum activity resists clear observation.

The Guiyi device generates a 0.5-volt storage window with the injection of merely one electron, meeting benchmarks set for commercial deployment and reaching the theoretical peak of charge-based storage defined by the one-electron-one-bit rule. Capable of lowering computing power draw at the hardware foundation, the device represents a new generation of core storage hardware aligned with the advancement of artificial general intelligence.

The research group has also put forward an original Density of States Scissors theory. It has experimentally uncovered an unprecedented anomalous quantum storage response for the first time globally. An intangible “quantum scissors” precisely cut away specific quantum states within energy space, causing those states to disappear entirely.

The findings build a distinct theoretical ecosystem dedicated to single-electron quantum storage and deliver an indispensable theoretical foundation to support the transition of quantum storage from laboratory research towards practical engineering implementation. Continued refinement of device architectures and manufacturing workflows will facilitate further validation of quantum memory technology for large-scale computing applications.