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arXiv · 2307.01571

Two-dimensional simulation of the spin-flip in the Kapitza-Dirac effect

Ping Ge·Sven Ahrens·Baifei Shen
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Abstract

Many calculations in strong field quantum field theory are carried out by using a simple field geometry, often neglecting the spacial field envelope. In this article, we simulate the electron diffraction quantum dynamics of the Kapitza-Dirac effect in a Gaussian beam standing light wave. The two-dimensional simulation is computed in a relativistic framework, by solving the Dirac equation with the fast Fourier transform split operator method. Except the numerical propagation method, our results are obtained without applying approximations and demonstrate that a spin-flip in the Kapitza-Dirac effect is possible. We further discuss properties, such as the validity of a plane wave approach for the theoretical description, the influence of the longitudinal polarization component due to laser beam focusing and higher order diffraction peaks in Kapitza-Dirac scattering.

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Ping Ge, Sven Ahrens, Baifei Shen. 2023-07-04. Two-dimensional simulation of the spin-flip in the Kapitza-Dirac effect. https://doi.org/10.1103/physreva.109.022240

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