Polarization control of above-threshold ionization spectrum in elliptically polarized two-color laser fields

Abstract

We study the above-threshold ionization (ATI) process of atoms exposed to fundamental and high-frequency lasers with arbitrary ellipticity by applying the frequency-domain theory. It is found that the angular-resolved ATI spectrum is sensitive to ellipticities of two lasers and emitted angles of the photoelectron. Particularly for the photon energy of the high-frequency laser more than atomic ionization potential, the width of plateau tends to a constant with increasing ellipticity of fundamental field, the dip structure disappears with increasing ellipticity of the high-frequency field. With the help of the quantum channel analysis, it is shown that the angular distribution depends mainly on the ellipticity of high-frequency field in the case that its frequency is high. Moreover, one can see that the maximal and minimal energies in quantum numerical results are in good agreement with the classical prediction. Our investigation may provide theoretical support for experimental research on polarization control of ionization in elliptically polarized two-color laser fields.