[1] Univ Quebec, Inst Natl Rech Sci, Varennes, PQ J3X 1S2, Canada
[2] Nankai Univ, Key Lab Weak Light Nonlinear Photon, Minist Educ, Tianjin 300457, Peoples R China
[3] Nankai Univ, TEDA Appl Phys Sch, Tianjin 300457, Peoples R China
[4] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94132 USA