[4] Bogoliubov N M, et al. Exact solution of generalized Tavis-Cummings models in quantum optics [J]. Phys. A:Math. Gen. 1996, 29:6305-6312
[5] Kuzmich A, et al. Spin squeezing in an ensemble of atoms illuminated with squeezed light [J]. Phys. Rev. Lett.,1997, 79:4782-4785
[6] Saito H, Ueda M. Squeezed few-photon states of the field generated from squeezed atoms [J]. Phys. Rev. A, 1999,58:3959-3974
[7] Fang Maofa, Zhou Peng, et al. Information entropy and squeezing of quantum fluctuation in a two-level atom [J].Chin. Phys. Lett., 2000, 17(11): 798-800