The generation of harmonics from two mixed laser fields of noncommensurate frequencies is analyzed. We address the case of the hydrogen atom irradiated both by a laser field of wavelength λ<sub>0</sub>=1231 nm with an intensity <i>I</i><sub>0</sub>=4×10<sup>13</sup> W cm<sup>−2</sup> and by a tunable laser field of wavelength approximately λ<sub>1</sub>=2071 nm with an intensity <i>I</i><sub>1</sub>≪<i>I</i><sub>0</sub>. We study the temporal profile and the efficiency of two-color harmonic generation far from the saturation regime. We focus on situations in which an even number of photons ω<sub>0</sub> are absorbed in association with the emission or absorption of one photon ω<sub>1</sub> of the second laser. The influence of the second laser on the production of the main harmonic spectrum is also analyzed.
© 1999 Optical Society of America
Rachel Hasbani, Eric Cormier, and Henri Bachau, "Generation of extreme ultraviolet tunable frequencies from mixed fields," J. Opt. Soc. Am. B 16, 1880-1885 (1999)