Blue- and red-shifts of the harmonics generated in laser-induced plasmas

Abstract

Abstract We demonstrate double-peak spectral splitting in high-order harmonics generated in graphite plasma, which is mainly attributed to the propagation effects of high harmonics in the ionizing medium. The splitting of high harmonics can also be interpreted as a result of the double-peak structure in the spectral profile of the propagated driving pulse. The shift and intensity of these peaks, compared with unshifted harmonics, depend on different parameters of the experiment like plasma density, the position of the focal plane, and laser intensity.