Rescattering processes for elliptical polarization: A quantum trajectory analysis

High-harmonic generation and high-order above-threshold ionization spectra calculated in the strong-field approximation are analyzed in terms of the c omplex space-time orbits that result from a saddle point analysis of the un derlying integrals. For elliptical polarization, the plateaus of the spectr a of high-harmonic generation and high-order above-threshold ionization eac h turn into a staircase of very similar appearance. Each step of the stair can be traced to a particular pair of orbits which are almost identical in both cases.