[1] X. Feng, Y. Liu, S. Yuan, G. Kai, W. Zhang, and X. Dong, Opt. Express 12, 3834 (2004).

[2] H. Chai, "All Solid State Dual-wavelength And Multiwavelength Laser" Master Thesis (Shandong Normal University, 2007).

[3] Y. J. Ding, P. Zhao, S. Ragam, D. Li, and I. B. Zotova, Chin. Opt. Lett. 9, 110004 (2011).

[4] W. Fan, Chin. Opt. Lett. 9, 110008 (2011).

[5] D. Creeden, J. C. McCarthy, P. A. Ketteridge, P. G. Schunemann, T. Southward, J. J. Komiak, and E. P. Chicklis, Opt. Express 15, 6478 (2007).

[6] Y. Qi, C. Liu, J. Zhou, W. Chen, J. Dong, Y. Wei, and Q. Lou, Acta Phys. Sin. 59, 3942 (2010).

[7] Q. Mao and J. W. Y. Lit, IEEE J. Quantum Electron. 39, 1252 (2003).

[8] W. Shi, M. A. Leigh, J. Zong, Z. Yao, D. T. Nguyen, A. Chavez-Pirson, and N. Peyghambarian, J. Sel. Top. Quantum Electron. 15, 377 (2009).

[9] J. Su, L. Hong, and J. Qian, Chinese J. Lasers 36, 643 (2009).

[10] Y. Liu, X. Feng, S. Yuan, G. Kai, and X. Dong, Opt. Express 12, 2056 (2004).

[11] D. Liu, N. Q. Ngo, X. Y. Dong, S. C. Tjin, and P. Shum, Appl. Phys. B 81, 807 (2005).

[12] J. Wang, L. Zhang, J. Hu, L. Si, J. Chen, X. Gu, and Y. Feng, Appl. Opt. 51, 3801 (2012).

[13] M. K. Smit, E. C. M. Pennings, and H. Blok, J. Lightwave Technol. 11, 1737 (1993).

[14] H. Cai, J. Zhou, T. Feng, G. Yao, Y. Qi, Q. Lou, J. Dong, and Y. Wei, Opt. Commun. 281, 4401 (2008).

[15] F. Liu, Y. Li, Q. Xing, C. Wang, M. Hu, L. Chai, and C. Wang, Chin. Opt. Lett. 9, S10201 (2011).

[16] X. Wang, "The Study of Terahertz Radiation Source based on Nonlinear Optical Difference- Frequency Generation" Master Thesis (Huazhong University of Science & Technology, 2011).

[17] C. Liu, Y. Qi, Y. Ding, J. Zhou, J. Dong, Y. Wei, and Q. Lou, Chin. Opt. Lett. 9, 031402 (2011).