New breakthroughs have been made in the field of photonic quantum chips in my country

Semiconductor systems have good scalable and integratable properties, and are considered to be one of the systems that may realize universal quantum computing. In recent years, a series of progress has been made in silicon-based semiconductor quantum computing, and the performance of qubits has been greatly improved. The fidelity of single-bit and two-bit logic gates has reached the threshold of fault-tolerant quantum computing. How to further expand the number of bits and improve the fidelity of bit reading has become a important issues in this field. Because of its ability to handle powerful light transmission, topological photonics has become a powerful platform for integrated optics, and has been further extended to the quantum world, with practical application prospects in photonic chip research. Strikingly, valley-contrast physics in topological photonic structures contributes to valley-dependent edge states, unidirectional coupling, and even valley-dependent wavelength division in topological junctions. A few days ago, Ren Xifeng's research group from the team of Academician Guo Guangcan of the University of Science and Technology of China cooperated with Dong Jianwen of Sun Yat-sen University, Dai Daozin of Zhejiang University and other research groups to realize quantum interference in the structure of energy valley-related topological insulator chips based on the photon energy valley Hall effect. related results to“Editors Recommended Articles' suggestion)”The form was published in the internationally renowned academic journal 'Physical Review Letters' on June 11. The research team designed and fabricated nanophotonic topological harpoon beamsplitters (HSBSs) based on a 120-degree curved interface and demonstrated the first on-chip valley-dependent quantum information process. With a 50/50 HSBS composed of two topologically distinct domain walls linked together, the research team achieved 0.956±0.006 high visibility two-photon quantum interference (ie Hong-Ou-Mandel interference). The research team also demonstrated a simple quantum photonic circuit and the generation of path-entangled states. This study shows that photonic valley states can be used for quantum information processing, and it is possible to realize more complex quantum circuits with valley-dependent photonic topological insulators, which provides a new approach for on-chip quantum information processing.