Terahertz Generation in Nonlinear Crystals with Mid-Infrared CO2 Laser - Lu, Yan-Zhao (彦兆 卢); Wang, Xin-Bing (新兵 王); Miao, Liang (亮苗); Zuo, Du-Luo (都罗 左); Cheng, Zu-Hai (祖海 程) (Chinese physics letters, 2011)