摘要We investigate the high-order harmonic generation from an atom prepared in a superposition of ground state and highly excited state. When the atom is irradiated by an ultrashort pulse, the cutoff position of the plateau in the harmonic spectrum is largely extended compared with the case that the atom is initially in the ground state. The physics of the extension of the high-order harmonic plateau can be interpreted by the spatial structure of the atomic initial wave packet. We can optimize the generation of high-order harmonics by substituting the excited state for a particular coherent superposition of some highly excited states to form a spatially localized excited wave packet.
Abstract：We investigate the high-order harmonic generation from an atom prepared in a superposition of ground state and highly excited state. When the atom is irradiated by an ultrashort pulse, the cutoff position of the plateau in the harmonic spectrum is largely extended compared with the case that the atom is initially in the ground state. The physics of the extension of the high-order harmonic plateau can be interpreted by the spatial structure of the atomic initial wave packet. We can optimize the generation of high-order harmonics by substituting the excited state for a particular coherent superposition of some highly excited states to form a spatially localized excited wave packet.
(Frequency conversion; harmonic generation, including higher-order harmonic generation)
引用本文:
YANG Yu-Jun;CHEN Ji-Gen;CHI Fang-Ping;ZHU Qi-Ren;ZHANG Hong-Xing;SUN Jia-Zhong. Ultrahigh Harmonic Generation from an Atom with Superposition of Ground State and Highly Excited States[J]. 中国物理快报, 2007, 24(6): 1537-1540.
YANG Yu-Jun, CHEN Ji-Gen, CHI Fang-Ping, ZHU Qi-Ren, ZHANG Hong-Xing, SUN Jia-Zhong. Ultrahigh Harmonic Generation from an Atom with Superposition of Ground State and Highly Excited States. Chin. Phys. Lett., 2007, 24(6): 1537-1540.
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2007, Vol. 24 
