Chinese scientists achieve breakthrough in quantum computing with 'Zhuangzi 2.0'

In the cinematic world of The Wandering Earth II, the super-intelligent AI "MOSS" navigates the impossible complexities of the universe with ease. While we aren't yet living in a sci-fi epic, a team of researchers from the Institute of Physics of the Chinese Academy of Sciences and Peking University has moved us one step closer to that level of control.

By using a sophisticated 78-qubit quantum processor named "Zhuangzi 2.0", the team has successfully mastered the "rhythm" of quantum systems — a feat that has long remained beyond the reach of the world's most powerful classical supercomputers. Their findings were published in the journal Nature on Wednesday.

The core of their discovery lies in a phenomenon known as "prethermalization". To understand this, imagine heating a block of ice. The ice doesn't immediately turn to water but lingers at 0 C despite constant heat as the energy breaks molecular bonds. Quantum systems exhibit a similar "plateau". When bombarded with external energy, qubits don't immediately collapse into chaos. Instead, they enter a brief, stable phase called prethermalization, where information is preserved and the system remains orderly.

The discovery of the "quantum plateau" is crucial for scientists because the greatest enemy of quantum computing is "heat" — the process where qubits lose their delicate information and become disorganized.

By applying a specific technique called Random Multipolar Driving, researchers learned how to adjust the "rhythm" and pattern of energy pulses sent into the chip to extend or shorten the stable phase — akin to assembling a complex puzzle whose pieces keep falling apart, where prethermalization acts as a temporary shield, and the technique provides a controllable window to complete calculations before collapsing into chaos.

The significance of this experiment extends far beyond the lab. While 78 qubits might seem small compared to the millions of bits in a smartphone, the complexity of their interactions is so vast that classical computers cannot accurately track them. As the quantum bits become entangled, the mathematical requirements for simulation grow exponentially, eventually hitting a wall that even the best silicon-based chips cannot climb.

Fan Heng, corresponding author of the study and a researcher at the Institute of Physics, emphasized the good performance of the "Zhuangzi 2.0" chip during the experiment. As a quantum system, the chip naturally manages these tasks, enabling scientists to observe complex dynamics in real-time.

"Achieving such a significant breakthrough cannot depend solely on stacking more bits; it necessitates systematic research throughout the entire process and collaborative efforts integrating experiments, numerical simulations, and theoretical analysis," he said, adding that this involves employing innovative scheme designs, developing specific techniques, and using appropriate chips.