'New way to understand the world' unlocked by quantum researchers

Chinese researchers have taken a significant step toward unlocking the potential of quantum computing by achieving a breakthrough in simulating a complex quantum state using photons.

Scientists at the University of Science and Technology of China, in Hefei, Anhui province, successfully realized the fractional quantum anomalous Hall state with photons, a feat previously only observed in electrons under specific conditions. Their findings were published in the journal Science on May 3.

The fractional quantum Hall state, first discovered in 1981, arises from the behavior of electrons in a special material under a strong magnetic field. Observing the phenomenon has been a major goal of condensed matter physics research.

The research team, led by professors Lu Chaoyang and Pan Jianwei, designed a system of 16 microscopic "photon boxes" on a tiny chip, confining a single photon within each box. This innovative "bottom-up" approach to quantum simulation allowed them to artificially create the desired quantum state.

"This technology, known as quantum simulation, is a key component of the 'second quantum revolution' and is expected to be applied to quantum computing in the near future," Pan said.

Quantum simulation offers a powerful tool for understanding and manipulating complex quantum systems, paving the way for advances in quantum information processing.

"We can combine atoms according to demand and design, thus providing a completely new way to understand the world," Pan said. "This approach allows us to actively construct quantum machines from the ground up, leading to the development of entirely new technologies."

Traditionally, studying the Hall effect required stringent experimental conditions, including extremely low temperatures and high-purity materials. The USTC team's method overcame those limitations by employing photons instead of electrons.

"With this artificially created photon system, control can be achieved, leading to higher flexibility and controllability," Lu said. "This allows us to precisely manipulate each component and gain a deeper understanding of quantum systems." Lu said their work has opened a new chapter in exploring exotic quantum phenomena.

"Using artificial photon boxes as basic units, we can create more of the strange quantum states that do not naturally exist in our world," Lu said. "This opens doors to research and discovery of entirely new scientific phenomena in the future."

Peng Chengchengcontributed to this story.

yandongjie@chinadaily.com.cn