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arXiv · 1204.0239

Spin dynamics in the Kapitza-Dirac effect

Sven Ahrens·Heiko Bauke·Christoph H. Keitel·Carsten Müller
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Abstract

Electron spin dynamics in Kapitza-Dirac scattering from a standing laser wave of high frequency and high intensity is studied. We develop a fully relativistic quantum theory of the electron motion based on the time-dependent Dirac equation. Distinct spin dynamics, with Rabi oscillations and complete spin-flip transitions, is demonstrated for Kapitza-Dirac scattering involving three photons in a parameter regime accessible to future high-power X-ray laser sources. The Rabi frequency and, thus, the diffraction pattern is shown to depend crucially on the spin degree of freedom.

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Sven Ahrens, Heiko Bauke, Christoph H. Keitel, Carsten Müller. 2012-03-27. Spin dynamics in the Kapitza-Dirac effect. https://doi.org/10.1103/physrevlett.109.043601

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