潘建伟教授研究组实现光学量子控制非门 [2010-07-11]

我院近代物理系潘建伟教授及其合作者利用四光子六量子比特的簇态实验实现了光学控制非门，该结果表明超纠缠的簇态是实现有效光学量子计算的有前途的候选者。文章发表在最新一期的物理学评论快报上(Physical Review Letters 104, 020501, 2010)，文章的标题和摘要如下：

Experimental realization of a controlled-NOT gate with four-photon six-qubit cluster states

Wei-Bo Gao1, Ping Xu1, Xing-Can Yao1, Otfried Gühne2,3, Adán Cabello4, Chao-Yang Lu1, Cheng-Zhi Peng1, Zeng-Bing Chen1, and Jian-Wei Pan1,5
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
2Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Technikerstraße 21A, A-6020 Innsbruck, Austria
3Institut für theoretische Physik, Universität Innsbruck, Technikerstraße 25, A-6020 Innsbruck, Austria
4Departamento de Física Aplicada II, Universidad de Sevilla, E-41012 Sevilla, Spain
5Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany

(Received 19 June 2009; Accepted Friday Dec 11, 2009; Published 13 January 2010)

We experimentally demonstrate an optical controlled-NOT (CNOT) gate with arbitrary single inputs based on a 4-photon 6-qubit cluster state entangled both in polarization and spatial modes. We first generate the 6-qubit state, and then, by performing single-qubit measurements, the CNOT gate is applied to arbitrary single input qubits. To characterize the performance of the gate, we estimate its quantum process fidelity and prove its entangling capability. In addition, our results show that the gate cannot be reproduced by local operations and classical communication. Our experiment shows that such hyper-entangled cluster states are promising candidates for efficient optical quantum computation.

加上张松斌等人发表的文章，最新一期的物理学评论快报同时发表了我系原子分子学科点的两篇文章。