According to foreign press, the group led by Prof. PAN Jianwei and his colleagues, Chen Yuao and LU Chaoyang, has managed to entangle eight photons in the so-called Schrödinger's cat state for the very first time, breaking the previous six-photon world record set up by the same group in 2007. This paper was published in Nature Photonics on 12 February.
Since the release of the preprint at arXiv.org in May 2011, it has attracted widespread attention in the academic community. Many science popular publishers, such as Institute of Physics, MIT technology review, Phys Org have reported this work: "In a game of one-upmanship, a Chinese team of physicists has figured out how to entangle eight photons simultaneously and to observe them in action; the previous record was six."
Developing practical quantum computation heavily depends on the coherent manipulation of multiple quantum states. The full entangled multipartite Schrödinger's cat state is an important benchmark of quantum control. With the long-term support from the China Academy of Sciences, Ministry of Science and Technology and National Natural Science Foundation of China, PAN Jianwei's team has been devoted to the research of this field. In 2004 and 2007 respectively, the team succeeded in manipulating the entanglement of five and six photons respectively, with the relevant papers published in Nature and Nature Physics. After four years of hard work, the team brought the manipulation of photons to another level, and created world's best entanglement photon source in terms of brightness and purity. In early 2011, the team was the first to realize the eight-photon Schrödinger's cat state. According to the authors, the eight-photon state should allow them to demonstrate a powerful way of correcting quantum errors called topological error correction.