中国物理B ›› 2014, Vol. 23 ›› Issue (6): 60302-060302.doi: 10.1088/1674-1056/23/6/060302

• GENERAL • 上一篇    下一篇

Quantum Fisher information and spin squeezing in one-axis twisting model

钟伟, 刘京, 马健, 王晓光   

  1. Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou 310027, China
  • 收稿日期:2013-12-03 修回日期:2014-02-20 出版日期:2014-06-15 发布日期:2014-06-15
  • 基金资助:
    Project supported by the National Basic Research Program of China (Grant No. 2012CB921602) and the National Natural Science Foundation of China (Grant Nos. 11025527 and 10935010).

Quantum Fisher information and spin squeezing in one-axis twisting model

Zhong Wei (钟伟), Liu Jing (刘京), Ma Jian (马健), Wang Xiao-Guang (王晓光)   

  1. Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou 310027, China
  • Received:2013-12-03 Revised:2014-02-20 Online:2014-06-15 Published:2014-06-15
  • Contact: Wang Xiao-Guang E-mail:xgwang@zimp.zju.edu.cn
  • Supported by:
    Project supported by the National Basic Research Program of China (Grant No. 2012CB921602) and the National Natural Science Foundation of China (Grant Nos. 11025527 and 10935010).

摘要: We investigate the dependence of the average parameter estimation precision (APEP), which is defined by the quantum Fisher information, on the polar angle of the initial coherent spin state |θ00> in a one-axis twisting model. Jin et al. [New J. Phys. 11 (2009) 073049] found that the spin squeezing sensitively depends on the polar angle θ0 of the initial coherent spin state. We show explicitly that the APEP is robust to the initial polar angle θ0 in the vicinity of π/2 and a near-Heisenberg limit ∝2/N in quantum single-parameter estimation may still be achieved for states created with the nonlinear evolution of the nonideal coherent spin states θ0π/2. Based on this model, we also consider the effects of the collective dephasing on spin squeezing and the APEP.

关键词: quantum Fisher information, spin squeezing, one-axis twisting model

Abstract: We investigate the dependence of the average parameter estimation precision (APEP), which is defined by the quantum Fisher information, on the polar angle of the initial coherent spin state |θ00> in a one-axis twisting model. Jin et al. [New J. Phys. 11 (2009) 073049] found that the spin squeezing sensitively depends on the polar angle θ0 of the initial coherent spin state. We show explicitly that the APEP is robust to the initial polar angle θ0 in the vicinity of π/2 and a near-Heisenberg limit ∝2/N in quantum single-parameter estimation may still be achieved for states created with the nonlinear evolution of the nonideal coherent spin states θ0π/2. Based on this model, we also consider the effects of the collective dephasing on spin squeezing and the APEP.

Key words: quantum Fisher information, spin squeezing, one-axis twisting model

中图分类号:  (Decoherence; open systems; quantum statistical methods)

  • 03.65.Yz
06.20.-f (Metrology) 42.50.Dv (Quantum state engineering and measurements)