[1] [1] H Hachisu, K Miyagishi, S G Porsev, et al.. Trapping of neutral mercury atoms and prospects for optical lattice clocks [J]. Phys Rev Lett, 2008, 100(5): 053001.

[2] [2] M Petersen, R Chicireanu, S T Dawkins, et al.. Doppler-free spectroscopy of the 1S0-3P0 optical clock transition in laser-cooled fermionic isotopes of neutral mercury [J]. Phys Rev Lett, 2008, 101(18): 183004.

[3] [3] P Villwock, S Siol, T Walther. Magneto-optical trapping of neutral mercury [J]. Eur Phys J D, 2011, 65(1-2): 251-255.

[4] [4] M V Romalis, W C Griffith, J P Jacobs, et al.. New limit on the permanent electric dipole Moment of 199Hg [J]. Phys Rev Lett, 2001, 86(12): 2505-2508.

[5] [5] E J Angstmann, V A Dzuba, V V Flambaum. Relativistic effects in two valence-electron atoms and ions and the search for variation of the fine-structure constant [J]. Phys Rev A, 2004, 70(1): 014102.

[6] [6] S Yin, H Liu, J Qian, T Hong, et al.. Observation and optimization of DAVLL spectra on the 1S0-3P1 transition of neutral mercury atom [J]. Opt Commun, 2012, 285(24): 5169-5174.

[7] [7] C Javaux, I G Hughes, G Lochead, et al.. Modulation-free pump-probe spectroscopy of strontium atoms [J]. Eur Phys J D, 2010, 57(2): 151-154.

[8] [8] G C Bjorklund. Frequency-modulation spectroscopy-new method for measuring weak absorptions and dispersions [J]. Opt Lett, 1980, 5(1): 15-17.

[9] [9] J H Shirley. Modulation transfer processes in optical heterodyne saturation spectroscopy [J]. Opt Lett, 1982, 7(11): 537-539.

[10] [10] D J McCarron, S A King, S L Cornish. Modulation transfer spectroscopy in atomic rubidium [J]. Meas Sci & Technol, 2008, 19(10): 105601.

[11] [11] K L Corwin, Z T Lu, C F Hand, et al.. Frequency-stabilized diode laser with the Zeeman shift in an atomic vapor [J]. Appl Opt, 1998, 37(15): 3295-3298.

[12] [12] A Millett-Sikking, I G Hughes, P Tierney, et al.. DAVLL lineshapes in atomic rubidium [J]. J Phys B, 2007, 40(1): 187-198.

[13] [13] G Wasik, W Gawlik, J Zachorowski, et al.. Laser frequency stabilization by Doppler-free magnetic dichroism [J]. Appl Phys B, 2002, 75(6-7): 613-619.

[14] [14] M Pichler, D C Hall. Simple laser frequency locking based on Doppler-free magnetically induced dichroism [J]. Opt Commun, 2012, 85(1): 50-53.

[15] [15] C Wieman, T W Hansch. Doppler-free laser polarization spectroscopy [J]. Phys Rev Lett, 1976, 36(20): 1170-1173.

[16] [16] H Liu, S Yin, K Liu, et al.. Magneto optical trap for neutral mercury atoms [J]. Chinese Physics B, 2003, 22(4): 043701.

[17] [17] H Liu, S Yin, J Qian, et al.. Optimization of Doppler-free magnetically induced dichroic locking spectroscopy on the 1S0-3P1 transition of a neutral mercury atom [J]. J Phys B, 2013, 46(8): 085005.

[18] [18] J M Supplee, E A Whittaker, W Lenth. Theoretical description of frequency-modulation and wavelength modulation spectroscopy [J]. Appl Opt, 1994, 33(27): 6294-6302.