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arXiv · 2103.07121

Beam focus and longitudinal polarization influence on spin dynamics in the Kapitza-Dirac effect

Sven Ahrens·Ziling Guan·Baifei Shen
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Abstract

We theoretically investigate the influence of a longitudinal laser polarization component from beam focusing on spin dynamics in Kapitza-Dirac scattering by solving the relativistic Dirac equation with time-dependent perturbation theory. The transverse spacial dependence of the longitudinal beam polarization component is accounted for, by approximating a Gaussian beam with plane-wave components. We find that corrections from a longitudinal laser beam polarization component approximately scale with the second power of the diffraction angle $\epsilon$, from which we conclude that a related influence from beam focusing can be made negligibly small for sufficiently low beam foci.

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Sven Ahrens, Ziling Guan, Baifei Shen. 2021-03-12. Beam focus and longitudinal polarization influence on spin dynamics in the Kapitza-Dirac effect. https://doi.org/10.1103/physreva.105.053123

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