China news agency, Hefei, November 23 (Reporter Wu Lan) - The 23rd reporter learned from the China University of Technology, the school leadership CAS academician Guo G Key Laboratory of Quantum Information Quantum entanglement in a major breakthrough in the study. Researchers successfully prepared eight-photon entangled state, refresh the preparation and operation of multi-photon entanglement number of world records. It is reported that the experiment from the preparation of high-brightness source of entanglement, which lasted more than three years. November 22, "Nature Communications" published online this research.

China Science entanglement researchers have improved methods for preparing the light source, the use of special non-linear crystals cut high luminance prepared entangled photon source and single mode fiber optical collection techniques to overcome the stability problem, re-use of the polarizing beam splitter Two-photon entangled photon entanglement cascade into eight other research problems, the final validation eight photon entanglement, quantum communication complexity through eight ports beyond the classic boundaries of experimental results, demonstrating the superiority of quantum entangle。

　　This achievement marks the scientists on the multi-photon entanglement preparation and manipulation of an unprecedented eight-photon level, in quantum communication networks, entanglement-based quantum computing quantum information obtained during such critical applications, while promoting the characteristics of quantum entanglement and classification basic physical issues.

Scientists say that quantum entanglement is to achieve the basis for a variety of quantum information processing. Since photon interference ability, communication speed, etc., multi-photon entangled state preparation and manipulation of quantum information has been important and difficult research in the field. Universal access to the world of the nonlinear crystal to generate multi-photon process entanglement, because this process is probabilistic, resulting in multi-photon entangled state difficulty will increase as the number of photons from multiplying large. Earlier, the international academic community has reported record up to six-photon entangled state prepared。