中国物理B ›› 2012, Vol. 21 ›› Issue (9): 90303-090303.doi: 10.1088/1674-1056/21/9/090303

• GENERAL • 上一篇    下一篇

Multipartite entanglement concentration of electron-spin states with CNOT gates

任宝藏, 华明, 李涛, 杜芳芳, 邓富国   

  1. Department of Physics, Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China
  • 收稿日期:2012-03-30 修回日期:2012-04-25 出版日期:2012-08-01 发布日期:2012-08-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10974020 and 11174039), the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-11-0031), and the Fundamental Research Funds for the Central Universities, China.

Multipartite entanglement concentration of electron-spin states with CNOT gates

Ren Bao-Cang (任宝藏), Hua Ming (华明), Li Tao (李涛), Du Fang-Fang (杜芳芳), Deng Fu-Guo (邓富国)   

  1. Department of Physics, Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China
  • Received:2012-03-30 Revised:2012-04-25 Online:2012-08-01 Published:2012-08-01
  • Contact: Deng Fu-Guo E-mail:fgdeng@bnu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10974020 and 11174039), the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-11-0031), and the Fundamental Research Funds for the Central Universities, China.

摘要: We propose a different entanglement concentration protocol (ECP) for nonlocal N-electron systems in a partially entangled Bell-type pure state using the CNOT gates and the projection measurements on an additional electron. For each nonlocal N-electron system, Alice first entangles it with the additional electron, and then she projects the additional electron onto an orthogonal basis for dividing the N-electron systems into two groups. In the first group, the N parties obtain a subset of N-electron systems in a maximally entangled state directly. In the second group, they obtain some less-entangled N-electron systems, which are the resource for the entanglement concentration in the next round. By iterating the entanglement concentration process several times, the present ECP has the maximal success probability, which is the theoretical limit of an ECP, equals to the entanglement of the partially entangled state, higher than the others. This ECP may be useful in quantum computers based on electron-spin systems in the future.

关键词: entanglement concentration, electron-spin states, decoherence, quantum communication

Abstract: We propose a different entanglement concentration protocol (ECP) for nonlocal N-electron systems in a partially entangled Bell-type pure state using the CNOT gates and the projection measurements on an additional electron. For each nonlocal N-electron system, Alice first entangles it with the additional electron, and then she projects the additional electron onto an orthogonal basis for dividing the N-electron systems into two groups. In the first group, the N parties obtain a subset of N-electron systems in a maximally entangled state directly. In the second group, they obtain some less-entangled N-electron systems, which are the resource for the entanglement concentration in the next round. By iterating the entanglement concentration process several times, the present ECP has the maximal success probability, which is the theoretical limit of an ECP, equals to the entanglement of the partially entangled state, higher than the others. This ECP may be useful in quantum computers based on electron-spin systems in the future.

Key words: entanglement concentration, electron-spin states, decoherence, quantum communication

中图分类号:  (Entanglement production and manipulation)

  • 03.67.Bg
03.65.Yz (Decoherence; open systems; quantum statistical methods) 03.67.Hk (Quantum communication)