Analytic Description of Laser Assisted Electron Scattering Plateau Spectra for Elliptical Polarization

We present an analytic description of laser-assisted electron scattering (LAES) for the case of an elliptically polarized laser field. A closed-form analytic formula describing plateau features in LAES is derived quantum mechanically in the low-frequency limit. This formula provides an analytic explanation for the oscillatory patterns of LAES cross sections in the high-energy part of the LAES spectra. This formula generalizes the result for a linearly polarized laser field presented in [1] to the case of elliptical polarization and confirms the possibility of factorizing the LAES cross section into the product of two atomic factors involving the field-free cross sections for elastic electron-atom scattering and a factor (insensitive to atomic parameters) describing the elliptically polarized laser-driven motion of the electron. These results provide a fully quantum justification of the classical rescattering scenario for LAES in an elliptically polarized laser field.\\ [4pt] [1] A.\,V. Flegel {\it at al.} J. Phys. B \textbf{42}, 241002 (2009).