Effect of multiple rescattering processes on harmonic emission in spatially inhomogeneous field

Zhang Cai-Ping^{1, 2}, Xia Chang-Long¹, Jia Xiang-Fu^{1, †}, Miao Xiang-Yang^{1, ‡}

(color online) (a) The time–frequency map is superimposed with the classical return energies for β = 0.0065: blue dots for the first rescattering, magenta dots for the second rescattering, and red dots for the continuum–continuum emission. (b) Sketch of the spatially inhomogeneous field with ϕ = 0. (c) The related time–frequency map from 1.5 o.c. to 3.5 o.c. with ϕ = π.