[2] Unruh W G. Maintaining coherence in quantum computers [J]. Phys. Rev. A, 1995, 51(2): 992-997

[3] Shor P W. Scheme for reducing decoherence in quantum computer [J]. Phys. Rev. A, 1995, 52(4): R2493-R2496

[8] Louisell W H. Quantum Statistical Properties of Radiation [M]. New York: John Wiley, 1973