Attosecond X-ray source generation by using spatially inhomogeneous field

Abstract

An efficient method for harmonic extension and attosecond X-ray source generation has been theoretically investigated by using the spatially inhomogeneous field. It is found that through moderating the inhomogeneities of the single-color or the two-color infrared fields, not only the harmonic cutoff has been remarkably enhanced, but also the single short quantum path has been selected to contribute to the harmonic. As a result, a series of sub-50as pulses from the XUV to the X-ray region can be obtained. Moreover, through investigating pulse duration effect on the harmonic emission, we find that the above harmonic extension and attosecond pulse generation can also be achieved by the multi-cycle spatially inhomogeneous fields, which is much better for experimental realization.