High harmonic generation in a two-color field composed of a pump field and a weak subsidiary high frequency field

Science in China Series A Mathematics (Impact Factor: 0.7). 01/2002; 45(1):76-81. DOI: 10.1360/02ys9008

ABSTRACT ‘Coherent control of high-harmonic generation in a two-color field’ has been widely concerned. Using split-operator algorithm,
we have calculated the high-harmonic generation for helium ion He+ in a two-color field which is composed of a driving field and a weak subsidiary high frequency field (Is = I0/100, (ω,13ω),...(ω, 120ω)) and found that such a field can produce much higher harmonic intensity, typically increasing the
harmonics corresponding to the incident frequency of the subsidiary field. The different effects coming from the different
subsidiary fields are calculated and analyzed. It is indicated that one of the important underlying mechanisms is high frequency
photon induced radiation.

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