中国物理B ›› 2009, Vol. 18 ›› Issue (2): 430-434.doi: 10.1088/1674-1056/18/2/009

• • 上一篇    下一篇

Decoherence of qubits: results beyond Markovian approximation

游建强1, 李铁夫2, 刘建设2, 李志坚2   

  1. (1)Department of Physics, Fudan University, Shanghai 200433, China; (2)Institute of Microelectronics, Tsinghua University, Beijing 100084, China
  • 收稿日期:2008-04-17 修回日期:2008-05-26 出版日期:2009-02-20 发布日期:2009-02-20
  • 基金资助:
    Project supported by the SRFDP, the PCSIRT, the NFRPC (Grant No 2006CB921205), the National Natural Science Foundation of China (Grant Nos 10534060 and 10625416) and the State Key Program for Basic Research of China (Grant Nos 2006CB921801 and 2006CB92110

Decoherence of qubits: results beyond Markovian approximation

Li Tie-Fu(李铁夫)a)†, You Jian-Qiang(游建强)b), Liu Jian-She(刘建设)a), and Li Zhi-Jian(李志坚)a)   

  1. a Institute of Microelectronics, Tsinghua University, Beijing 100084, China; b Department of Physics, Fudan University, Shanghai 200433, China
  • Received:2008-04-17 Revised:2008-05-26 Online:2009-02-20 Published:2009-02-20
  • Supported by:
    Project supported by the SRFDP, the PCSIRT, the NFRPC (Grant No 2006CB921205), the National Natural Science Foundation of China (Grant Nos 10534060 and 10625416) and the State Key Program for Basic Research of China (Grant Nos 2006CB921801 and 2006CB92110

摘要: In this paper the master equation method is used to calculate the relaxation and decoherence times of a qubit. The results are beyond Markovian approximation, where the noise spectrum is assumed to be wide-band, so that they are valid for not only the wide- but also the narrow-band noises, which may be the main decoherence source in solid-state qubits. Moreover, for some special cases, analytical results can be achieved, which are consistent with those derived by others.

关键词: qubit, decoherence, master equation

Abstract: In this paper the master equation method is used to calculate the relaxation and decoherence times of a qubit. The results are beyond Markovian approximation, where the noise spectrum is assumed to be wide-band, so that they are valid for not only the wide- but also the narrow-band noises, which may be the main decoherence source in solid-state qubits. Moreover, for some special cases, analytical results can be achieved, which are consistent with those derived by others.

Key words: qubit, decoherence, master equation

中图分类号:  (Quantum computation architectures and implementations)

  • 03.67.Lx
03.65.Yz (Decoherence; open systems; quantum statistical methods) 05.40.-a (Fluctuation phenomena, random processes, noise, and Brownian motion) 02.50.Ga (Markov processes) 02.30.-f (Function theory, analysis)