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2. 1. 2007.
Above-threshold detachment by a two-color bicircular laser field
Above-threshold detachment of electrons from negative ions by a bicircular laser field is analyzed within the strong-field approximation. A bicircular field consists of two counter-rotating circularly polarized fields with angular frequencies rω and sω with integer r and s. The energy and angle resolved spectra of the detached electron are invariant with respect to a rotation by the angle 360°/(r+s). The results obtained are explained in terms of the interference of contributions to the T matrix from different complex solutions of the saddle-point equation.