J4 ›› 2018, Vol. 35 ›› Issue (4): 439-443.

• 量子光学 • 上一篇    下一篇

N=4的自旋链上量子信息在磁场中的传输研究

王清亮,任恒峰   

  1. 忻州师范学院物理系,山西 忻州,034000
  • 收稿日期:2017-06-05 修回日期:2017-10-18 出版日期:2018-07-28 发布日期:2018-07-12
  • 通讯作者: 王清亮(1979-),山东莘县人,硕士,副教授,主要从事量子信息方面的研究。 E-mail:angql19790511@163.com
  • 基金资助:

    Supported by Xinzhou Teachers University Foundation(忻州师院院级基金,JGZD201602)

Research on quantum information transfer in spin chain with N=4 in low-intensity magnetic field

WANG Qingliang, REN Hengfeng   

  1. Department of Physics, Xinzhou Teachers University, Xinzhou 034000, China
  • Received:2017-06-05 Revised:2017-10-18 Published:2018-07-28 Online:2018-07-12

摘要:

基于量子信息在自旋链上的传输理论,研究了两种磁场情形下N=4的自旋链上单比特量子信息传输受到的影响。对置于磁场中的自旋链,将体系的哈密度算符进行对角化,进而考虑磁场中信息传输的动力学行为。结果表明空间均匀、时间恒定的弱磁场不会对该模型中量子信息的传输产生任何影响;各格点处大小逐差为B、方向关于链中心对称的弱磁场对量子信息的传输有至关重要的作用。尤其是对于保真度为1的完美传输,磁场参量B很大程度上决定了传输得以实现的条件。

关键词: 量子信息;信息传输;动力学演化;自旋链

Abstract:

Based on the theory of quantum information transfer in spin chain, the effects of two types of magnetic field are investigated for a single qubit information transfer in spin chain with N=4 in . For the spin chain in some magnetic fields, Hamiltonian of the system is diagonalized, and the dynamic behavior of information transfer is considered in magnetic field. Results show that the low-intensity magnetic field which is uniform in space and constant in time has nothing to do with quantum information transfer. The low-intensity magnetic field with the difference value B between the nearest-neighbor lattices and the symmetrical direction to center of the spin chain plays a key role for quantum information transfer. Particularly, for the perfect transfer with fidelity value of 1, the transferring condition is dependent on the magnetic parameter B to a certain extent.

Key words: quantum information; information transfer; dynamical evolution; spin chain

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