[1] [1] M. O. Scully, M. S. Zubairy. Quantum Optics [M]. Cambridge University Press, 1997, Chapter 7. 220～247

[2] [2] H. R. Gray, R. M. Whitley, C. R. Stroud, Jr.. Coherent trapping of atomic populations [J]. Opt.Lett., 1978, 3(6):218～220

[3] [3] E. Arimondo. Coherent population trapping in laser spectroscopy [J]. Progress in Optics, 1996, 35:259～288

[4] [4] K. J. Boller, A. Imamoglu, S. E. Harris. Observation of electromagnetically induced transparency [J]. Phy. Revs. Lett., 1991, 66(20):2593～2596

[5] [5] Yang Xihua. Investigation of transient properties of electromagnetically induced transparency with different pump laser energy [J]. Chinese J. Lasers, 2004, 31(7):811～814

[6] [6] Zhang Lianshui, Yang Lijun, Li Xiaoli et al.. Suppressing power broadening of electromagnetically induced transparency by utilizing microwave field [J]. Acta Optica Sinica, 2007, 27(7):1305～1308

[7] [7] Zhang Liying, Liu Zhengdong, Chen Jun. Electromagnetically induced transparency of quasi-Λ-type four-level atom system at low-light levels [J]. Acta Optica Sinica, 2006, 26(9):1419～1423

[8] [8] O. A. Kocharovskaya, Y. I. Khanin. Coherent amplification of an ultrashort pulse in a three-level medium without a population inversion [J]. JETP Lett., 1988, 48(11):630～634

[9] [9] M. O. Scully, S. Y. Zhu, A. Gavrielides. Degenerate quantum-beat laser: Lasing without inversion and inversion without lasing [J]. Phys. Rev. Lett., 1989, 62(24):2813～2816

[10] [10] A. Kuhn, S. Steuerwald, K. Bergmann. Coherent population transfer in NO with pulsed lasers: the consequences of hyperfine structure, Doppler broadening and electromagnetically induced absorption [J]. European Phys. J. D, 1998, 1(1):57～70

[11] [11] Wang Yanhua, Yan Shubin, Wang Junmin et al.. Electromagnetically induced absorption of degenerate two-level system in a cesium vapor cell [J]. Chinese J. Lasers, 2004, 31(9):1063～1069

[12] [12] Lihui Jin, Shangqing Gong, Yueping Niu et al.. Electromagnetically induced transparency and controllable group velocity in a five-level atomic system [J]. Chin. Opt. Lett., 2006, 4(5):252～254

[13] [13] Jie Ma, Yanting Zhao, Lirong Wang et al.. Absorption resonances in Λ-type three-level system in cesium vapor cell with buffer gas [J]. Chin. Opt. Lett., 2006, 4(1):55～58

[14] [14] M. Merimaa, T. Lindvall, I. Tittonen et al.. All-optical atomic clock based on coherent population trapping in 85Rb [J]. J. Opt. Soc. Am. B, 2003, 20(2):273～279

[15] [15] R. Lutwak, P. Vlitas, M. Varghes et al.. The MAC-a miniature atomic clock [C]. D. Coler ed. in Proceedings of 2005 Joint IEEE International Frequency Control (UFFC) Symposium and the 37th Annual Precise Time & Time Interval (PTTI) Systems & Applications Meeting. Vancouver,BC,Canada, 2005. 752～757

[16] [16] J. Vanier, M. W. Levine, D. Janssen et al.. On the use of intensity optical pumping and coherent population trapping techniques in the implementation of atomic frequency standards [J]. IEEE Trans. Instrum. Meas., 2003, 52(3):822～831

[17] [17] J. Vanier. Atomic clocks based on coherent population trapping: a review [J]. Appl. Phys. B, 2005, 81(4):421～442

[18] [18] Liu Guobin, Du Runchang, Liu Chaoyang et al.. CPT magnetometer with atomic energy level modulation [J]. Chin. Phys. Lett., 2008, 25(2):472～474

[19] [19] J. Vanier, M. W. Levine, D. Janssen et al.. Contrast and linewidth of the coherent population trapping transmission hyperfine resonance line in 87Rb: effect of optical pumping [J]. Phys. Rev. A, 2003, 67(6):065801

[20] [20] P. Trmblay, C. Jacques. Optical pumping with two finite linewidth lasers [J]. Phys. Rev. A, 1990, 41(9):4989～4999

[21] [21] Sihong Gu, J. A. Behr. Off-Raman resonance effects on hyperfine coherences [J]. Phys. Rev. A, 2003, 68(1):015804