[1] Mcpherson A, Gibson G, Jara H,et al. Studies of multiphoton production of vacuum-ultraviolet radiation in the rare gases.J Opt Soc Am(B), 1987,4(4):595～601

[2] Chang Zenghu, Rundquist A, Wang Haiwen,et al. Generation of coherent soft X-rays at 2.7 nm using high harmonics.Phys Rev Lett,1997,79(16):2967～2970

[4] Wang Yingsong, Liu Yaqing, Yang Xiaodong, et al. Spectral splitting in high-order harmonic generation. Phys Rev(A),2000,62(6):063806-1～0638026-4

[6] Lompre L A,L′Huillier A,Ferray M,et al.High-order harmonic generation in xenon:Intensity and propagation effects.J Opt Soc Am(B),1990,7(5):754～761